Therapeutic compounds and uses thereof

ABSTRACT

The invention relates to compounds of formula (I) and salts thereof: 
     
       
         
         
             
             
         
       
     
     wherein R 1 -R 3  have any of the values defined in the specification. The compounds and salts are useful for treating PCAF mediated disorders and/or GCN5 mediated disorders. The invention also provides pharmaceutical compositions comprising a compound of formula (I), or a pharmaceutically acceptable salt thereof, as well as and methods of using said compounds, salts, or compositions in the treatment of various disorders.

PRIORITY OF INVENTION

This application claims priority from U.S. Provisional Patent Application No. 62/101,953, filed Jan. 9, 2015, which is hereby incorporated by reference in its entirety.

TECHNICAL FIELD OF THE INVENTION

The present invention relates to compounds useful as inhibitors of P300/CBP-associated factor (PCAF) as well as its closely related homolog GCN5, and methods of treating cancer using such inhibitors.

BACKGROUND OF THE INVENTION

Chromatin is a complex combination of DNA and protein that makes up chromosomes. It is found inside the nuclei of eukaryotic cells and is divided between heterochromatin (condensed) and euchromatin (extended) forms. The major components of chromatin are DNA and proteins. Histones are the chief protein components of chromatin, acting as spools around which DNA winds. The functions of chromatin are to package DNA into a smaller volume to fit in the cell, to strengthen the DNA to allow mitosis and meiosis, and to serve as a mechanism to control expression and DNA replication. The chromatin structure is controlled by a series of post-translational modifications to histone proteins, notably histones H3 and H4, and most commonly within the “histone tails” which extend beyond the core nucleosome structure. Histone tails tend to be free for protein-protein interaction and are also the portion of the histone most prone to post-translational modification. These modifications include acetylation, methylation, phosphorylation, ubiquitinylation, and SUMOylation. These epigenetic marks are written and erased by specific enzymes that place the tags on specific residues within the histone tail, thereby forming an epigenetic code, which is then interpreted by the cell to allow gene specific regulation of chromatin structure and thereby transcription.

Of all classes of proteins, histones are amongst the most susceptible to post-translational modification. Histone modifications are dynamic, as they can be added or removed in response to specific stimuli, and these modifications direct both structural changes to chromatin and alterations in gene transcription. Distinct classes of enzymes, namely histone acetyltransferases (HATs) and histone deacetylases (HDACs), acetylate or de-acetylate specific histone lysine residues (Struhl K., Genes Dev., 1989, 12, 5, 599-606).

Bromodomains, which are approximately 110 amino acids long, are found in a large number of chromatin-associated proteins and have been identified in approximately 70 human proteins, often adjacent to other protein motifs (Jeanmougin F., et al., Trends Biochem. Sci., 1997, 22, 5, 151-153; and Tamkun J. W., et al., Cell, 1992, 7, 3, 561-572). Interactions between bromodomains and modified histones may be an important mechanism underlying chromatin structural changes and gene regulation. Bromodomain-containing proteins have been implicated in disease processes including cancer, inflammation and viral replication. See, e.g., Prinjha et al., Trends Pharm. Sci., 33(3):146-153 (2012) and Muller et al., Expert Rev., 13(29):1-20 (September 2011).

Cell-type specificity and proper tissue functionality requires the tight control of distinct transcriptional programs that are intimately influenced by their environment. Alterations to this transcriptional homeostasis are directly associated with numerous disease states, most notably cancer, immuno-inflammation, neurological disorders, and metabolic diseases. Bromodomains reside within key chromatin modifying complexes that serve to control distinctive disease-associated transcriptional pathways. This is highlighted by the observation that mutations in bromodomain-containing proteins are linked to cancer, as well as immune and neurologic dysfunction. Hence, the selective inhibition of bromodomains across a specific family, such as the selective inhibition of a bromodomain of PCAF, creates varied opportunities as novel therapeutic agents in human dysfunction.

There is a need for treatments for cancer, immunological disorders, and other PCAF bromodomain related diseases. There is also a need for treatments for GCN5 mediated disorders.

SUMMARY OF THE INVENTION

One aspect includes a compound of formula (I), or a pharmaceutically acceptable salt thereof:

wherein:

R¹ is selected from the group consisting of methyl, chloro, and bromo;

R² is C₁₋₄alkyl, C₂₋₄alkenyl, cyclopropyl, or cyclopropylmethyl; and

R³ is a 3-12 membered saturated or partially unsaturated heterocyclyl, which heterocyclyl is optionally substituted with one or more groups independently selected from the group consisting of C₁₋₆alkyl, C₂₋₆alkenyl, C₂₋₆alkynyl, carbocyclyl, heterocyclyl, oxo, halo, —NO₂, —N(R^(b))₂, —CN, —C(O)—N(R^(b))₂, —S(O)—N(R^(b))₂, —S(O)₂—N(R^(b))₂, —O—R^(b), —S—R^(b), —O—C(O)—R^(b), —C(O)—R^(b), —C(O)—OR^(b), —S(O)—R^(b), —S(O)₂—R^(b), —N(R^(b))—C(O)—R^(b), —N(R^(b))—S(O)—R^(b), —N(R^(b))—C(O)—N(R^(b))₂, and —N(R^(b))—S(O)₂—R^(b), wherein any C₁₋₆alkyl, C₂₋₆alkenyl, C₂₋₆alkynyl, carbocyclyl, and heterocyclyl is optionally substituted with one or more groups independently selected from the group consisting of R^(b), oxo, halo, —NO₂, —N(R^(b))₂, —CN, —C(O)—N(R^(b))₂, —S(O)—N(R^(b))₂, —S(O)₂—N(R^(b))₂, —O—R^(b), —S—R^(b), —O—C(O)—R^(b), —C(O)—R^(b), —C(O)—O—R^(b), —S(O)—R^(b), —S(O)₂—R^(b), —N(R^(b))—C(O)—R^(b), —N(R^(b))—S(O)—R^(b), —N(R^(b))—C(O)—N(R^(b))₂, and —N(R^(b))—S(O)₂—R^(b);

each R^(b) is independently selected from the group consisting of hydrogen, C₁₋₄alkyl, C₂₋₆alkenyl, C₂₋₄alkynyl, C₁₋₆alkoxy, carbocyclyl, and heterocyclyl, wherein each C₁₋₆alkyl, C₂₋₆alkenyl, C₂₋₆alkynyl, C₁₋₄alkoxy, carbocyclyl, and heterocyclyl is optionally substituted with one or more groups independently selected from the group consisting of R^(c), oxo, halo, —NO₂, —N(R^(c))₂, —CN, —C(O)—N(R′)₂, —S(O)—N(R^(c))₂, —S(O)₂—N(R^(c))₂, —O—R^(c), —S—R^(c), —O—C(O)—R^(c), —C(O)—R^(c), —C(O)—OR^(c), —S(O)—R^(c), —S(O)₂—R^(c), —N(R^(c))—C(O)—R^(c), —N(R^(c))—S(O)—R^(c), —N(R^(c))—C(O)—N(R^(c))₂, and —N(R^(c))—S(O)₂—R^(c); or two R^(c) are taken together with the nitrogen to which they are attached to form a heterocyclyl that is optionally substituted with one or more groups independently selected from the group consisting of oxo, halo and C₁₋₃alkyl that is optionally substituted with one or more groups independently selected from the group consisting of oxo and halo; and each R^(c) is independently selected from the group consisting of hydrogen, C₁₋₆alkyl, C₂₋₆alkenyl, C₂₋₄alkynyl, C₁₋₆alkoxy, carbocyclyl, and heterocyclyl, wherein each C₁₋₆alkyl, C₂₋₆alkenyl, C₂₋₆alkynyl, C₁₋₆alkoxy, carbocyclyl, and heterocyclyl is optionally substituted with one or more groups independently selected from the group consisting of oxo, halo, amino, hydroxy, C₁₋₆alkoxy, carbocyclyl, heterocyclyl, and C₁-C₆ alkyl that is optionally substituted with one or more groups independently selected from the group consisting of oxo and halo; or two Re are taken together with the nitrogen to which they are attached to form a heterocyclyl that is optionally substituted with one or more groups independently selected from the group consisting of oxo, halo and C₁₋₃alkyl that is optionally substituted with one or more groups independently selected from the group consisting of oxo and halo.

Another aspect includes a composition comprising a compound of formula (I) or a pharmaceutically acceptable salt thereof, and a pharmaceutically acceptable adjuvant, carrier, or vehicle.

Another aspect includes a method for treating a PCAF mediated disorder or a GCN5 mediated disorder in an animal comprising administering to the animal a compound of formula (I), or a pharmaceutically acceptable salt thereof

Another aspect includes a compound of formula (I) or a pharmaceutically acceptable salt thereof for use in medical therapy.

Another aspect includes a compound of formula (I) or a pharmaceutically acceptable salt thereof for the prophylactic or therapeutic treatment of a PCAF mediated disorder.

Another aspect includes the use of a compound of formula (I) or a pharmaceutically acceptable salt thereof to prepare a medicament for treating a PCAF mediated disorder in an animal (e.g., a mammal such as a human).

Another aspect includes compounds for the study of PCAF.

Another aspect includes novel compounds of formula (I) and salts thereof.

Another aspect includes a method of a) increasing efficacy of a cancer treatment comprising a cytotoxic agent in an animal (e.g., a mammal such as a human), b) delaying or preventing development of cancer resistance to a cytotoxic agent in an animal (e.g., a mammal such as a human), or c) extending the duration of response to a cancer therapy in an animal (e.g., a mammal such as a human) comprising administering to the animal an effective amount of a compound of formula (I) or a pharmaceutically acceptable salt thereof.

Another aspect includes a compound of formula (I) or a pharmaceutically acceptable salt thereof as described in claim 1 for a) increasing efficacy of a cancer treatment comprising a cytotoxic agent in an animal (e.g., a mammal such as a human), b) delaying or preventing development of cancer resistance to a cytotoxic agent in an animal (e.g., a mammal such as a human), or c) extending the duration of response to a cancer therapy in an animal (e.g., a mammal such as a human).

Another aspect includes the use of a compound of formula (I) or a pharmaceutically acceptable salt thereof to prepare a medicament for a) increasing efficacy of a cancer treatment comprising a cytotoxic agent in an animal (e.g., a mammal such as a human), b) delaying or preventing development of cancer resistance to a cytotoxic agent in an animal (e.g., a mammal such as a human), or c) extending the duration of response to a cancer therapy in an animal (e.g., a mammal such as a human).

Another aspect includes a method of treating cancer in an individual (e.g., a patient) comprising administering to the individual (a) a compound of formula (I) or a pharmaceutically acceptable salt thereof and (b) a cytotoxic agent.

Another aspect includes a compound of formula (I) or a pharmaceutically acceptable salt thereof for the prophylactic or therapeutic treatment of cancer in combination with a cytotoxic agent.

Another aspect includes the use of a compound of formula (I) or a pharmaceutically acceptable salt thereof to prepare a medicament for treating cancer in combination with a cytotoxic agent.

Another aspect includes synthetic intermediates and synthetic processes disclosed herein that are useful for preparing a compound of formula (I) or a salt thereof.

DETAILED DESCRIPTION Compounds and Definitions

Definitions and terms are described in more detail below. Chemical elements are identified in accordance with the Periodic Table of the Elements, CAS version, Handbook of Chemistry and Physics, 75^(th) Ed.

Unless otherwise stated, compounds of formula I include enantiomeric, diastereomeric and geometric (or conformational) isomeric forms of a given structure. For example, the R and S configurations for each asymmetric center, Z and E double bond isomers, Z and E conformational isomers, single stereochemical isomers, as well as enantiomeric, diastereomeric, and geometric (or conformational) mixtures are included. Unless otherwise stated, all tautomeric forms of structures depicted herein are included. Additionally, unless otherwise stated, structures depicted herein are also meant to include compounds that differ only in the presence of one or more isotopically enriched atoms. For example, compounds of formula I, wherein the independent replacement or enrichment of one or more hydrogen by deuterium or tritium, carbon by ¹³C- or ¹⁴C carbon, nitrogen by a ¹⁵N nitrogen, sulfur by a ³³S, ³⁴S or ³⁶S sulfur, oxygen by a ¹⁷O or ¹⁸O oxygen, or fluorine by a ¹⁸F are included. Such compounds are useful, for example, as analytical tools, as probes in biological assays, or as therapeutic agents.

Where a particular enantiomer is described, it may, in certain embodiments be provided substantially free of the corresponding enantiomer, and may also be referred to as “optically enriched.” “Optically-enriched,” as used herein, means that the mixture of enantiomers is made up of a significantly greater proportion of one enantiomer, and may be described by enantiomeric excess (ee %). In certain embodiments, the mixture of enantiomers is made up of at least about 90% by weight of a given enantiomer (about 90% ee). In other embodiments, the mixture of enantiomers is made up of at least about 95%, 98% or 99% by weight of a given enantiomer (about 95%, 98% or 99% ee). Enantiomers and diastereomers may be isolated from racemic mixtures by any method known to those skilled in the art, including recrystallization from solvents in which one stereoisomer is more soluble than the other, chiral high pressure liquid chromatography (HPLC), supercritical fluid chromatography (SFC), the formation and crystallization of chiral salts, which are then separated by any of the above methods, or prepared by asymmetric syntheses and optionally further enriched. See, for example, Jacques et al., Enantiomers, Racemates and Resolutions (Wiley Interscience, New York, 1981); Wilen, et al., Tetrahedron 33:2725 (1977); Eliel, E. L. Stereochemistry of Carbon Compounds (McGraw-Hill, N Y, 1962); Wilen, S. H. Tables of Resolving Agents and Optical Resolutions p. 268 (E. L. Eliel, Ed., Univ. of Notre Dame Press, Notre Dame, Ind. 1972).

The term “heteroatom” means any atom independently selected from an atom other than carbon or hydrogen, for example, one or more of oxygen, sulfur, nitrogen, phosphorus or silicon (including any oxidized form of nitrogen, sulfur, phosphorus or silicon; and the quaternized form of any nitrogen).

The terms “halo” and “halogen” as used herein refer to an atom selected from fluorine (fluoro, —F), chlorine (chloro, —Cl), bromine (bromo, —Br) and iodine (iodo, —I).

The term “oxo” refers to ═O.

The term “unsaturated”, as used herein, means that a moiety has one or more units of unsaturation.

The term “carbocyclyl” used alone or as part of a larger moiety, refers to a saturated, partially unsaturated, or aromatic (e.g., aryl) ring system having 3 to 20 carbon atoms. In one embodiment, carbocyclyl includes 3 to 12 carbon atoms (C₃-C₁₂). In another embodiment, carbocyclyl includes C₃-C₈, C₃-C₁₀ or C₅-C₁₀. In other embodiment, carbocyclyl, as a monocycle, includes C₃-C₈, C₃-C₆ or C₅-C₆. In another embodiment, carbocyclyl, as a bicycle, includes C₇-C₁₂. In another embodiment, carbocyclyl, as a spiro system, includes C₅-C₁₂. Examples of monocyclic carbocyclyls include cyclopropyl, cyclobutyl, cyclopentyl, 1-cyclopent-1-enyl, 1-cyclopent-2-enyl, 1-cyclopent-3-enyl, cyclohexyl, perdeuteriocyclohexyl, 1-cyclohex-1-enyl, 1-cyclohex-2-enyl, 1-cyclohex-3-enyl, cyclohexadienyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl, cycloundecyl, phenyl, and cyclododecyl; bicyclic carbocyclyls having 7 to 12 ring atoms include [4,3], [4,4], [4,5], [5,5], [5,6] or [6,6] ring systems, for example bicyclo[2.2.1]heptane, bicyclo[2.2.2]octane, naphthalene, and bicyclo[3.2.2]nonane; and spiro carbocyclyls include spiro[2.2]pentane, spiro[2.3]hexane, spiro[2.4]heptane, spiro[2.5]octane and spiro[4.5]decane. The term carbocyclyl includes aryl ring systems as defined herein. The term carbocycyl also includes cycloalkyl rings (e.g. saturated or partially unsaturated mono-, bi-, bridged-, or spiro-carbocycles).

The term “alkyl,” as used herein, refers to a saturated linear or branched-chain hydrocarbon radical. In one embodiment, the alkyl radical is one to eighteen carbon atoms (C₁-C₁₈). In other embodiments, the alkyl radical is C₀-C₆, C₀-C₅, C₀-C₃, C₁-C₁₂, C₁-C₁₀, C₁-C₈, C₁-C₆, C₁-C₅, C₁-C₄ or C₁-C₃. C₀ alkyl refers to a bond. Examples of alkyl groups include methyl (Me, —CH₃), ethyl (Et, —CH₂CH₃), 1-propyl (n-Pr, n-propyl, —CH₂CH₂CH₃), 2-propyl (i-Pr, i-propyl, —CH(CH₃)₂), 1-butyl (n-Bu, n-butyl, —CH₂CH₂CH₂CH₃), 2-methyl-1-propyl (i-Bu, i-butyl, —CH₂CH(CH₃)₂), 2-butyl (s-Bu, s-butyl, —CH(CH₃)CH₂CH₃), 2-methyl-2-propyl (t-Bu, t-butyl, —C(CH₃)₃), 1-pentyl (n-pentyl, —CH₂CH₂CH₂CH₂CH₃), 2-pentyl (—CH(CH₃)CH₂CH₂CH₃), 3-pentyl (—CH(CH₂CH₃)₂), 2-methyl-2-butyl (—C(CH₃)₂CH₂CH₃), 3-methyl-2-butyl (—CH(CH₃)CH(CH₃)₂), 3-methyl-1-butyl (—CH₂CH₂CH(CH₃)₂), 2-methyl-1-butyl (—CH₂CH(CH₃)CH₂CH₃), I-hexyl (—CH₂CH₂CH₂CH₂CH₂CH₃), 2-hexyl (—CH(CH₃)CH₂CH₂CH₂CH₃), 3-hexyl (—CH(CH₂CH₃)(CH₂CH₂CH₃)), 2-methyl-2-pentyl (—C(CH₃)₂CH₂CH₂CH₃), 3-methyl-2-pentyl (—CH(CH₃)CH(CH₃)CH₂CH₃), 4-methyl-2-pentyl (—CH(CH₃)CH₂CH(CH₃)₂), 3-methyl-3-pentyl (—C(CH₃)(CH₂CH₃)₂), 2-methyl-3-pentyl (—CH(CH₂CH₃)CH(CH₃)₂), 2,3-dimethyl-2-butyl (—C(CH₃)₂CH(CH₃)₂), 3,3-dimethyl-2-butyl (—CH(CH₃)C(CH₃)₃, heptyl, octyl, nonyl, decyl, undecyl and dodecyl.

The term “alkenyl,” as used herein, denotes a linear or branched-chain hydrocarbon radical with at least one carbon-carbon double bond. An alkenyl includes radicals having “cis” and “trans” orientations, or alternatively, “E” and “Z” orientations. In one example, the alkenyl radical is two to eighteen carbon atoms (C₂-C₁₈). In other examples, the alkenyl radical is C₂-C₁₂, C₂-C₁₀, C₂-C₈, C₂-C₆ or C₂-C₃. Examples include, but are not limited to, ethenyl or vinyl (—CH═CH₂), prop-1-enyl (—CH═CHCH₃), prop-2-enyl (—CH₂CH═CH₂), 2-methylprop-1-enyl, but-1-enyl, but-2-enyl, but-3-enyl, buta-1,3-dienyl, 2-methylbuta-1,3-diene, hex-1-enyl, hex-2-enyl, hex-3-enyl, hex-4-enyl and hexa-1,3-dienyl.

The term “alkynyl,” as used herein, refers to a linear or branched hydrocarbon radical with at least one carbon-carbon triple bond. In one example, the alkynyl radical is two to eighteen carbon atoms (C₂-C₁₈). In other examples, the alkynyl radical is C₂-C₁₂, C₂-C₁₀, C₂-C₈, C₂-C₆ or C₂-C₃. Examples include, but are not limited to, ethynyl (—C≡CH), prop-1-ynyl (—C≡C≡CH₃), prop-2-ynyl (propargyl, —CH₂C≡CH), but-1-ynyl, but-2-ynyl and but-3-ynyl.

The term “alkoxy” refers to a linear or branched radical represented by the formula —OR in which R is alkyl, alkenyl, alkynyl or carbocycyl. Alkoxy groups include methoxy, ethoxy, propoxy, isopropoxy, and cyclopropoxy.

The term “haloalkyl,” as used herein, refers to an alkyl as defined herein that is substituted with one or more (e.g. 1, 2, 3, or 4) halo groups.

The term “aryl” used alone or as part of a larger moiety as in “arylalkyl”, “arylalkoxy”, or “aryloxyalkyl”, refers to a monocyclic, bicyclic or tricyclic, carbon ring system, that includes fused rings, wherein at least one ring in the system is aromatic. The term “aryl” may be used interchangeably with the term “aryl ring”. In one embodiment, aryl includes groups having 6-20 carbon atoms (C₆-C₂₀ aryl). In another embodiment, aryl includes groups having 6-10 carbon atoms (C₆-C₁₀ aryl). Examples of aryl groups include phenyl, naphthyl, anthracyl, biphenyl, phenanthrenyl, naphthacenyl, 1,2,3,4-tetrahydronaphthalenyl, 1H-indenyl, 2,3-dihydro-1H-indenyl, and the like, which may be substituted or independently substituted by one or more substituents described herein. A particular aryl is phenyl. In another embodiment aryl includes an aryl ring fused to one or more carbocyclic rings, such as indanyl, phthalimidyl, naphthimidyl, phenantriidinyl, or tetrahydronaphthyl, and the like, where the radical or point of attachment is on an aromatic ring.

The term “heteroaryl” used alone or as part of a larger moiety, e.g., “heteroarylalkyl”, or “heteroarylalkoxy”, refers to a monocyclic, bicyclic or tricyclic ring system having 5 to 14 ring atoms, wherein at least one ring is aromatic and contains at least one heteroatom. In one embodiment, heteroaryl includes 4-6 membered monocyclic aromatic groups where one or more ring atoms is nitrogen, sulfur or oxygen that is independently optionally substituted. In another embodiment, heteroaryl includes 5-6 membered monocyclic aromatic groups where one or more ring atoms is nitrogen, sulfur or oxygen that is independently optionally substituted. In some embodiments, the heteroaryl group is a C₁-C₂₀ heteroaryl group, where the heteroaryl ring contains 1-20 carbon atoms and the remaining ring atoms include one or more nitrogen, sulfur, or oxygen atoms. Example heteroaryl groups include thienyl, furyl, imidazolyl, pyrazolyl, thiazolyl, isothiazolyl, oxazolyl, isoxazolyl, triazolyl, thiadiazolyl, oxadiazolyl, tetrazolyl, thiatriazolyl, oxatriazolyl, pyridyl, pyrimidyl, pyrazinyl, pyridazinyl, triazinyl, tetrazinyl, tetrazolo[1,5-b]pyridazinyl, imidazol[1,2-a]pyrimidinyl, purinyl, benzoxazolyl, benzofuryl, benzothiazolyl, benzothiadiazolyl, benzotriazolyl, benzoimidazolyl, indolyl, 1,3-thiazol-2-yl, 1,3,4-triazol-5-yl, 1,3-oxazol-2-yl, 1,3,4-oxadiazol-5-yl, 1,2,4-oxadiazol-5-yl, 1,3,4-thiadiazol-5-yl, 1H-tetrazol-5-yl, 1,2,3-triazol-5-yl, pyrid-2-yl N-oxide, and pyrazolo[4,3-c]pyridinyl. The terms “heteroaryl” also includes groups in which a heteroaryl is fused to one or more aryl, carbocyclyl, or heterocyclyl rings, where the radical or point of attachment is on the heteroaryl ring. Nonlimiting examples include indolyl, isoindolyl, benzothienyl, benzofuranyl, dibenzofuranyl, indazolyl, benzimidazolyl, benzthiazolyl, quinolyl, isoquinolyl, cinnolinyl, phthalazinyl, quinazolinyl, quinoxalinyl, 4H-quinolizinyl, carbazolyl, acridinyl, phenazinyl, phenothiazinyl, phenoxazinyl, tetrahydroquinolinyl, and tetrahydroisoquinolinyl. A heteroaryl group may be mono-, bi- or tri-cyclic.

As used herein, the term “heterocyclyl” refers to a “carbocyclyl” as defined herein, wherein one or more (e.g. 1, 2, 3, or 4) carbon atoms have been replaced with a heteroatom (e.g. O, N, or S). In some embodiments, a heterocyclyl refers to a saturated ring system, such as a 3 to 12 membered saturated heterocyclyl ring system, or a 3 to 8 membered saturated heterocyclyl ring system. In some embodiments, a heterocyclyl refers to a 5 to 8 membered saturated heterocyclyl ring system. In some embodiments, a heterocyclyl refers to a 5 to 6 membered saturated heterocyclyl ring system. In some embodiments, a heterocyclyl refers to a heteroaryl ring system, such as a 5 to 14 membered heteroaryl ring system. A heterocyclyl can optionally be substituted with one or more substituents independently selected from those defined herein.

In one example, heterocyclyl includes 3-12 ring atoms and includes monocycles, bicycles, tricycles, bridged, and spiro ring systems, wherein the ring atoms are carbon, and one to five ring atoms is a heteroatom selected from nitrogen, sulfur or oxygen, which is independently optionally substituted by one or more groups. In one example, heterocyclyl includes 1 to 4 heteroatoms. In another example, heterocyclyl includes 3- to 7-membered monocycles having one or more heteroatoms selected from nitrogen, sulfur or oxygen. In another example, heterocyclyl includes 4- to 6-membered monocycles having one or more heteroatoms selected from nitrogen, sulfur or oxygen. In another example, heterocyclyl includes 3-membered monocycles. In another example, heterocyclyl includes 4-membered monocycles.

In another example, heterocyclyl includes 5-6 membered monocycles. In one example, the heterocyclyl group includes 0 to 3 double bonds. Any nitrogen or sulfur heteroatom may optionally be oxidized (e.g. NO, SO, SO₂), and any nitrogen heteroatom may optionally be quaternized (e.g. [NR₄]⁺Cl⁻, [NR₄]⁺OH⁺). Example heterocyclyls include oxiranyl, aziridinyl, thiiranyl, azetidinyl, oxetanyl, thietanyl, 1,2-dithietanyl, 1,3-dithietanyl, pyrrolidinyl, dihydro-1H-pyrrolyl, dihydrofuranyl, tetrahydrofuranyl, dihydrothienyl, tetrahydrothienyl, imidazolidinyl, piperidinyl, piperazinyl, morpholinyl, thiomorpholinyl, 1,1-dioxo-thiomorpholinyl, dihydropyranyl, tetrahydropyranyl, hexahydrothiopyranyl, hexahydropyrimidinyl, oxazinanyl, thiazinanyl, thioxanyl, homopiperazinyl, homopiperidinyl, azepanyl, oxepanyl, thiepanyl, oxazepinyl, oxazepanyl, diazepanyl, 1,4-diazepanyl, diazepinyl, thiazepinyl, thiazepanyl, tetrahydrothiopyranyl, oxazolidinyl, thiazolidinyl, isothiazolidinyl, 1,1-dioxoisothiazolidinonyl, oxazolidinonyl, imidazolidinonyl, 4,5,6,7-tetrahydro[2H]indazolyl, tetrahydrobenzoimidazolyl, 4,5,6,7-tetrahydrobenzo[d]imidazolyl, 1,6-dihydroimidazol[4,5-d]pyrrolo[2,3-b]pyridinyl, thiazinyl, oxazinyl, thiadiazinyl, oxadiazinyl, dithiazinyl, dioxazinyl, oxathiazinyl, thiatriazinyl, oxatriazinyl, dithiadiazinyl, imidazolinyl, dihydropyrimidyl, tetrahydropyrimidyl, 1-pyrrolinyl, 2-pyrrolinyl, 3-pyrrolinyl, indolinyl, thiapyranyl, 2H-pyranyl, 4H-pyranyl, dioxanyl, 1,3-dioxolanyl, pyrazolinyl, pyrazolidinyl, dithianyl, dithiolanyl, pyrimidinonyl, pyrimidindionyl, pyrimidin-2,4-dionyl, piperazinonyl, piperazindionyl, pyrazolidinylimidazolinyl, 3-azabicyclo[3.1.0]hexanyl, 3,6-diazabicyclo[3.1.1]heptanyl, 6-azabicyclo[3.1.1]heptanyl, 3-azabicyclo[3.1.1]heptanyl, 3-azabicyclo[4.1.0]heptanyl, azabicyclo[2.2.2]hexanyl, 2-azabicyclo[3.2.1]octanyl, 8-azabicyclo[3.2.1]octanyl, 2-azabicyclo[2.2.2]octanyl, 8-azabicyclo[2.2.2]octanyl, 7-oxabicyclo[2.2.1]heptane, azaspiro[3.5]nonanyl, azaspiro[2.5]octanyl, azaspiro[4.5]decanyl, I-azaspiro[4.5]decan-2-only, azaspiro[5.5]undecanyl, tetrahydroindolyl, octahydroindolyl, tetrahydroisoindolyl, tetrahydroindazolyl, 1,1-dioxohexahydrothiopyranyl. Examples of 5-membered heterocyclyls containing a sulfur or oxygen atom and one to three nitrogen atoms are thiazolyl, including thiazol-2-yl and thiazol-2-yl N-oxide, thiadiazolyl, including 1,3,4-thiadiazol-5-yl and 1,2,4-thiadiazol-5-yl, oxazolyl, for example oxazol-2-yl, and oxadiazolyl, such as 1,3,4-oxadiazol-5-yl, and 1,2,4-oxadiazol-5-yl. Example 5-membered ring heterocyclyls containing 2 to 4 nitrogen atoms include imidazolyl, such as imidazol-2-yl; triazolyl, such as 1,3,4-triazol-5-yl; 1,2,3-triazol-5-yl, 1,2,4-triazol-5-yl, and tetrazolyl, such as 1H-tetrazol-5-yl. Example benzo-fused 5-membered heterocyclyls are benzoxazol-2-yl, benzthiazol-2-yl and benzimidazol-2-yl. Example 6-membered heterocyclyls contain one to three nitrogen atoms and optionally a sulfur or oxygen atom, for example pyridyl, such as pyrid-2-yl, pyrid-3-yl, and pyrid-4-yl; pyrimidyl, such as pyrimid-2-yl and pyrimid-4-yl; triazinyl, such as 1,3,4-triazin-2-yl and 1,3,5-triazin-4-yl; pyridazinyl, in particular pyridazin-3-yl, and pyrazinyl. The pyridine N-oxides and pyridazine N-oxides and the pyridyl, pyrimid-2-yl, pyrimid-4-yl, pyridazinyl and the 1,3,4-triazin-2-yl groups, are other example heterocyclyl groups.

As used herein, the term “partially unsaturated” refers to a ring moiety that includes at least one double or triple bond between ring atoms but the ring moiety is not aromatic.

As used herein, the term “inhibitor” refers to a compound that binds to and inhibits PCAF with measurable affinity and activity. In certain embodiments, an inhibitor has an IC₅₀ or binding constant of less about 20 μM, less than about 1 μM, less than about 500 nM, less than about 100 nM, or less than about 10 nM.

The terms “measurable affinity” and “measurably inhibit,” as used herein, refer to a measurable reduction in activity (e.g., reduction in recognition of lysine acetyl recognition of chromatin) of the bromodomain PCAF between: (i) a sample comprising a compound of formula I or composition thereof and such bromodomain, and (ii) an equivalent sample comprising such bromodomain, in the absence of said compound, or composition thereof.

“Pharmaceutically acceptable salts” include both acid and base addition salts. It is to be understood that when a compound or Example herein is shown as a specific salt, the corresponding free-base, as well as other salts of the corresponding free-base (including pharmaceutically acceptable salts of the corresponding free-base) are contemplated.

“Pharmaceutically acceptable acid addition salt” refers to those salts which retain the biological effectiveness and properties of the free bases and which are not biologically or otherwise undesirable, formed with inorganic acids such as hydrochloric acid, hydrobromic acid, sulfuric acid, nitric acid, carbonic acid, phosphoric acid and the like, and organic acids may be selected from aliphatic, cycloaliphatic, aromatic, araliphatic, heterocyclic, carboxylic, and sulfonic classes of organic acids such as formic acid, acetic acid, propionic acid, glycolic acid, gluconic acid, lactic acid, pyruvic acid, oxalic acid, malic acid, maleic acid, maloneic acid, succinic acid, fumaric acid, tartaric acid, citric acid, aspartic acid, ascorbic acid, glutamic acid, anthranilic acid, benzoic acid, cinnamic acid, mandelic acid, embonic acid, phenylacetic acid, methanesulfonic acid, ethanesulfonic acid, benzenesulfonic acid, p-toluenesulfonic acid, salicyclic acid and the like.

“Pharmaceutically acceptable base addition salts” include those derived from inorganic bases such as sodium, potassium, lithium, ammonium, calcium, magnesium, iron, zinc, copper, manganese, aluminum salts and the like. Particularly base addition salts are the ammonium, potassium, sodium, calcium and magnesium salts. Salts derived from pharmaceutically acceptable organic nontoxic bases includes salts of primary, secondary, and tertiary amines, substituted amines including naturally occurring substituted amines, cyclic amines and basic ion exchange resins, such as isopropylamine, trimethylamine, diethylamine, triethylamine, tripropylamine, ethanolamine, 2-diethylaminoethanol, tromethamine, dicyclohexylamine, lysine, arginine, histidine, caffeine, procaine, hydrabamine, choline, betaine, ethylenediamine, glucosamine, methylglucamine, theobromine, purines, piperizine, piperidine, N-ethylpiperidine, polyamine resins and the like. Particular organic non-toxic bases are isopropylamine, diethylamine, ethanolamine, tromethamine, dicyclohexylamine, choline, and caffeine.

The term “tautomer” or “tautomeric form” refers to structural isomers of different energies which are interconvertible via a low energy barrier. For example, proton tautomers (also known as prototropic tautomers) include interconversions via migration of a proton, such as keto-enol and imine-enamine isomerizations. Valence tautomers include interconversions by reorganization of some of the bonding electrons.

A “solvate” refers to an association or complex of one or more solvent molecules and a compound of the present invention. Examples of solvents include water, isopropanol, ethanol, methanol, DMSO, ethyl acetate, acetic acid and ethanolamine. The term “hydrate” refers to the complex where the solvent molecule is water.

“Therapeutically effective amount” refers to an amount of a compound of the present invention that (i) treats the particular disease, condition or disorder, (ii) attenuates, ameliorates or eliminates one or more symptoms of the particular disease, condition, or disorder, or (iii) delays the onset of one or more symptoms of the particular disease, condition or disorder described herein. In the case of cancer, the therapeutically effective amount of the drug may reduce the number of cancer cells; reduce the tumor size; inhibit (i.e., slow to some extent and preferably stop) cancer cell infiltration into peripheral organs; inhibit (i.e., slow to some extent and preferably stop) tumor metastasis; inhibit, to some extent, tumor growth; and/or relieve to some extent one or more of the symptoms associated with the cancer. For cancer therapy, efficacy can, for example, be measured by assessing the time to disease progression (TTP) and/or determining the response rate (RR). In the case of immunological disorders, the therapeutic effective amount is an amount sufficient to decrease or alleviate an allergic disorder, the symptoms of an autoimmune and/or inflammatory disease, or the symptoms of an acute inflammatory reaction (e.g. asthma).

“Treatment” (and variations such as “treat” or “treating”) refers to clinical intervention in an attempt to alter the natural course of the individual or cell being treated, and can be performed either for prophylaxis or during the course of clinical pathology. Desirable effects of treatment include one or more of preventing recurrence of disease, alleviation of symptoms, diminishment of any direct or indirect pathological consequences of the disease, stabilized (i.e., not worsening) state of disease, preventing metastasis, decreasing the rate of disease progression, amelioration or palliation of the disease state, prolonging survival as compared to expected survival if not receiving treatment and remission or improved prognosis. In certain embodiments, a compound of formula I is used to delay development of a disease or disorder or to slow the progression of a disease or disorder. Those individuals in need of treatment include those already with the condition or disorder as well as those prone to have the condition or disorder, (for example, through a genetic mutation or aberrant expression of a gene or protein).

“PCAF bromodomain inhibitor” or refers to a compound that binds to the PCAF bromodomain and inhibits and/or reduces a biological activity of PCAF. In some embodiments, PCAF bromodomain inhibitor binds to PCAF primarily (e.g., solely) through contacts and/or interactions with the PCAF bromodomain. In some embodiments, PCAF bromodomain inhibitor substantially or completely inhibits the biological activity of PCAF. In some embodiments, the biological activity is binding of the bromodomain of PCAF to chromatin (e.g., histones associated with DNA) and/or another acetylated protein.

The terms “PCAF” and “P300/CBP-Associated Factor”, “K(lysine)acetyltransferase 2B”, “KAT2B”, “Histone Acetylase PCAF”, “Histone Acetyltransferase PCAF”, “Lysine Acetyltransferase 2B”, “P/CAF”, “EC 2.3.1.48”, “CAF”, “CREBBP-Associated Factor”, and “Histone Acetyltransferase KAT2B” as used herein, may be used interchangeably, and refer to any native PCAF from any vertebrate souce, including mammals such as primates (e.g. humans) and rodents (e.g. mice and rats), unless otherwise indicated. The term encompasses “full-length” unprocessed PCAF as well as any form of PCAF that results from processing in the cell. The term also encompasses naturally occurring variants of PCAF, e.g. splice variants or allelic variants.

The term GCN5 includes GCN5L2, PCAF-b, KAT2A, STAF97, and the like.

As used herein, “a” or “an” means one or more, unless clearly indicated otherwise. As used herein, “another” means at least a second or more.

Exemplary Values

In one embodiment R¹ is chloro.

In one embodiment R² is methyl, isopropyl, ethyl, cyclopropylmethyl, 2-buten-1-yl.

In one embodiment R³ is a piperidyl ring or azepanyl ring, which piperidyl ring or azepanyl ring is optionally substituted with one or more groups independently selected from the group consisting of C₁₋₆alkyl, C₂₋₆alkenyl, C₂₋₆alkynyl, carbocyclyl, heterocyclyl, oxo, halo, —NO₂, —N(R^(b))₂, —CN, —C(O)—N(R^(b))₂, —S(O)—N(R^(b))₂, —S(O)₂—N(R^(b))₂, —O—R^(b), —S—R^(b), —O—C(O)—R^(b), —C(O)—R^(b), —C(O)—OR^(b), —S(O)—R^(b), —S(O)₂—R^(b), —N(R^(b))—C(O)—R^(b), —N(R^(b))—S(O)—R^(b), —N(R^(b))—C(O)—N(R^(b))₂, and —N(R^(b))—S(O)₂—R^(b), wherein any C₁₋₆alkyl, C₂₋₆alkenyl, C₂₋₆alkynyl, carbocyclyl, and heterocyclyl is optionally substituted with one or more groups independently selected from the group consisting of R^(b), oxo, halo, —NO₂, —N(R^(b))₂, —CN, —C(O)—N(R^(b))₂, —S(O)—N(R^(b))₂, —S(O)₂—N(R^(b))₂, —O—R^(b), —S—R^(b), —O—C(O)—R^(b), —C(O)—R^(b), —C(O)—O—R^(b), —S(O)—R^(b), —S(O)₂—R^(b), —N(R^(b))—C(O)—R^(b), —N(R^(b))—S(O)—R^(b), —N(R^(b))—C(O)—N(R^(b))₂, and —N(R^(b))—S(O)₂—R^(b).

In one embodiment R³ is a piperidyl ring, which piperidyl ring is optionally substituted with one or more groups independently selected from the group consisting of C₁₋₆alkyl, C₂₋₆alkenyl, C₂₋₆alkynyl, carbocyclyl, heterocyclyl, oxo, halo, —NO₂, —N(R^(b))₂, —CN, —C(O)—N(R^(b))₂, —S(O)—N(R^(b))₂, —S(O)₂—N(R^(b))₂, —O—R^(b), —S—R^(b), —O—C(O)—R^(b), —C(O)—R^(b), —C(O)—OR^(b), —S(O)—R^(b), —S(O)₂—R^(b), —N(R^(b))—C(O)—R^(b), —N(R^(b))—S(O)—R^(b), —N(R^(b))—C(O)—N(R^(b))₂, and —N(R^(b))—S(O)₂—R^(b), wherein any C₁₋₆alkyl, C₂₋₆alkenyl, C₂₋₆alkynyl, carbocyclyl, and heterocyclyl is optionally substituted with one or more groups independently selected from the group consisting of R^(b), oxo, halo, —NO₂, —N(R^(b))₂, —CN, —C(O)—N(R^(b))₂, —S(O)—N(R^(b))₂, —S(O)₂—N(R^(b))₂, —O—R^(b), —S—R^(b), —O—C(O)—R^(b), —C(O)—R^(b), —C(O)—O—R^(b), —S(O)—R^(b), —S(O)₂—R^(b), —N(R^(b))—C(O)—R^(b), —N(R^(b))—S(O)—R^(b), —N(R^(b))—C(O)—N(R^(b))₂, and —N(R^(b))—S(O)₂—R^(b);

In one embodiment R³ is a azepanyl ring, which azepanyl ring is optionally substituted with one or more groups independently selected from the group consisting of C₁₋₆alkyl, C₂₋₆alkenyl, C₂₋₆alkynyl, carbocyclyl, heterocyclyl, oxo, halo, —NO₂, —N(R^(b))₂, —CN, —C(O)—N(R^(b))₂, —S(O)—N(R^(b))₂, —S(O)₂—N(R^(b))₂, —O—R^(b), —S—R^(b), —O—C(O)—R^(b), —C(O)—R^(b), —C(O)—OR^(b), —S(O)—R^(b), —S(O)₂—R^(b), —N(R^(b))—C(O)—R^(b), —N(R^(b))—S(O)—R^(b), —N(R^(b))—C(O)—N(R^(b))₂, and —N(R^(b))—S(O)₂—R^(b), wherein any C₁₋₆alkyl, C₂₋₆alkenyl, C₂₋₆alkynyl, carbocyclyl, and heterocyclyl is optionally substituted with one or more groups independently selected from the group consisting of R^(b), oxo, halo, —NO₂, —N(R^(b))₂, —CN, —C(O)—N(R^(b))₂, —S(O)—N(R^(b))₂, —S(O)₂—N(R^(b))₂, —O—R^(b), —S—R^(b), —O—C(O)—R^(b), —C(O)—R^(b), —C(O)—O—R^(b), —S(O)—R^(b), —S(O)₂—R^(b), —N(R^(b))—C(O)—R^(b), —N(R^(b))—S(O)—R^(b), —N(R^(b))—C(O)—N(R^(b))₂, and —N(R^(b))—S(O)₂—R^(b).

In one embodiment R³ is a piperidyl ring or azepanyl ring, which piperidyl ring or azepanyl ring is optionally substituted with one or more groups independently selected from the group consisting of C₁₋₆alkyl, wherein any C₁₋₆alkyl is optionally substituted with one or more groups independently selected from the group consisting of R^(b), oxo, halo, —NO₂, —N(R^(b))₂, —CN, —C(O)—N(R^(b))₂, —S(O)—N(R^(b))₂, —S(O)₂—N(R^(b))₂, —O—R^(b), —S—R^(b), —O—C(O)—R^(b), —C(O)—R^(b), —C(O)—O—R^(b), —S(O)—R^(b), —S(O)₂—R^(b), —N(R^(b))—C(O)—R^(b), —N(R^(b))—S(O)—R^(b), —N(R^(b))—C(O)—N(R^(b))₂, and —N(R^(b))—S(O)₂—R^(b).

In one embodiment R³ is a piperidyl ring, which piperidyl ring is optionally substituted with one or more groups independently selected from the group consisting of C₁₋₆alkyl, wherein any C₁₋₆alkyl is optionally substituted with one or more groups independently selected from the group consisting of R^(b), oxo, halo, —NO₂, —N(R^(b))₂, —CN, —C(O)—N(R^(b))₂, —S(O)—N(R^(b))₂, —S(O)₂—N(R^(b))₂, —O—R^(b), —S—R^(b), —O—C(O)—R^(b), —C(O)—R^(b), —C(O)—O—R^(b), —S(O)—R^(b), —S(O)₂—R^(b), —N(R^(b))—C(O)—R^(b), —N(R^(b))—S(O)—R^(b), —N(R^(b))—C(O)—N(R^(b))₂, and —N(R^(b))—S(O)₂—R^(b).

In one embodiment R³ is a azepanyl ring, which azepanyl ring is optionally substituted with one or more groups independently selected from the group consisting of C₁₋₆alkyl, wherein any C₁₋₆alkyl is optionally substituted with one or more groups independently selected from the group consisting of R^(b), oxo, halo, —NO₂, —N(R^(b))₂, —CN, —C(O)—N(R^(b))₂, —S(O)—N(R^(b))₂, —S(O)₂—N(R^(b))₂, —O—R^(b), —S—R^(b), —O—C(O)—R^(b), —C(O)—R^(b), —C(O)—O—R^(b), —S(O)—R^(b), —S(O)₂—R^(b), —N(R^(b))—C(O)—R^(b), —N(R^(b))—S(O)—R^(b), —N(R^(b))—C(O)—N(R^(b))₂, and —N(R^(b))—S(O)₂—R^(b).

In one embodiment R³ is a piperidyl ring or azepanyl ring, which piperidyl ring or azepanyl ring is optionally substituted with one or more groups independently selected from the group consisting of C₁₋₆alkyl, wherein any C₁₋₆alkyl is optionally substituted with one or more groups independently selected from the group consisting of R^(b).

In one embodiment R³ is a piperidyl ring, which piperidyl ring is optionally substituted with one or more groups independently selected from the group consisting of C₁₋₆alkyl, wherein any C₁₋₆alkyl is optionally substituted with one or more groups independently selected from the group consisting of R^(b).

In one embodiment R³ is a azepanyl ring, which azepanyl ring is optionally substituted with one or more groups independently selected from the group consisting of C₁₋₆alkyl, wherein any C₁₋₆alkyl is optionally substituted with one or more groups independently selected from the group consisting of R^(b).

In one embodiment:

R¹ is selected from the group consisting of methyl, chloro, and bromo;

R² is C₁₋₄alkyl, C₂₋₄alkenyl, cyclopropyl, or cyclopropylmethyl; and

R³ is a piperidyl ring or azepanyl ring, which piperidyl ring or azepanyl ring is optionally substituted with one or more groups independently selected from the group consisting of C₁₋₆alkyl, wherein any C₁₋₆alkyl is optionally substituted with one or more groups independently selected from the group consisting of R^(b).

In one embodiment:

R¹ is selected from the group consisting of methyl, chloro, and bromo;

R² is C₁₋₄alkyl, C₂₋₄alkenyl, cyclopropyl, or cyclopropylmethyl; and

R³ is a piperidyl ring, which piperidyl ring is optionally substituted with one or more groups independently selected from the group consisting of C₁₋₆alkyl, wherein any C₁₋₆alkyl is optionally substituted with one or more groups independently selected from the group consisting of R^(b).

In one embodiment:

R¹ is selected from the group consisting of methyl, chloro, and bromo;

R² is C₁₋₄alkyl, C₂₋₄alkenyl, cyclopropyl, or cyclopropylmethyl; and

R³ is a azepanyl ring, which azepanyl ring is optionally substituted with one or more groups independently selected from the group consisting of C₁₋₆alkyl, wherein any C₁₋₆alkyl is optionally substituted with one or more groups independently selected from the group consisting of R^(b).

In one embodiment R³ is selected from the group consisting of:

In one embodiment R³ is selected from the group consisting of:

In one embodiment the compound is selected from the group consisting of:

and salts thereof.

In one embodiment the compound is not a compound selected from the group consisting of:

In certain embodiments the compound of Formula (I) is a compound as described in the Examples herein, or a freebase or salt thereof.

Uses, Formulation and Administration

Pharmaceutically Acceptable Compositions

Another aspect includes a pharmaceutical composition comprising a compound of formula (I) or a pharmaceutically acceptable salt thereof. In one embodiment, the composition further comprises a pharmaceutically acceptable carrier, adjuvant, or vehicle. In another embodiment, the composition further comprises an amount of the compound effective to measurably inhibit a bromodomain of PCAF. In certain embodiments, the composition is formulated for administration to a patient in need thereof.

The term “patient” or “individual” as used herein, refers to an animal, such as a mammal, such as a human. In one embodiment, patient or individual refers to a human.

The term “pharmaceutically acceptable carrier, adjuvant, or vehicle” refers to a non-toxic carrier, adjuvant, or vehicle that does not destroy the pharmacological activity of the compound with which it is formulated. Pharmaceutically acceptable carriers, adjuvants or vehicles that may be used in the compositions of this invention include, but are not limited to, ion exchangers, alumina, aluminum stearate, lecithin, serum proteins, such as human serum albumin, buffer substances such as phosphates, glycine, sorbic acid, potassium sorbate, partial glyceride mixtures of saturated vegetable fatty acids, water, salts or electrolytes, such as protamine sulfate, disodium hydrogen phosphate, potassium hydrogen phosphate, sodium chloride, zinc salts, colloidal silica, magnesium trisilicate, polyvinyl pyrrolidone, cellulose-based substances, polyethylene glycol, sodium carboxymethylcellulose, polyacrylates, waxes, polyethylene-polyoxypropylene-block polymers, polyethylene glycol and wool fat.

Compositions comprising a compound of formula I or salt thereof may be administered orally, parenterally, by inhalation spray, topically, transdermally, rectally, nasally, buccally, sublingually, vaginally, intraperitoneal, intrapulmonary, intradermal, epidural or via an implanted reservoir. The term “parenteral” as used herein includes subcutaneous, intravenous, intramuscular, intra-articular, intra-synovial, intrasternal, intrathecal, intrahepatic, intralesional and intracranial injection or infusion techniques.

In one embodiment, the composition comprising a compound of formula I or salt thereof is formulated as a solid dosage form for oral administration. Solid dosage forms for oral administration include capsules, tablets, pills, powders, and granules. In certain embodiments, the solid oral dosage form comprising a compound of formula (I) or a salt thereof further comprises one or more of (i) an inert, pharmaceutically acceptable excipient or carrier, such as sodium citrate or dicalcium phosphate, and (ii) filler or extender such as starches, lactose, sucrose, glucose, mannitol, or silicic acid, (iii) binders such as carboxymethylcellulose, alginates, gelatin, polyvinylpyrrolidinone, sucrose or acacia, (iv) humectants such as glycerol, (v) disintegrating agent such as agar, calcium carbonate, potato or tapioca starch, alginic acid, certain silicates or sodium carbonate, (vi) solution retarding agents such as paraffin, (vii) absorption accelerators such as quaternary ammonium salts, (viii) a wetting agent such as cetyl alcohol or glycerol monostearate, (ix) absorbent such as kaolin or bentonite clay, and (x) lubricant such as talc, calcium stearate, magnesium stearate, polyethylene glycols or sodium lauryl sulfate. In certain embodiments, the solid oral dosage form is formulated as capsules, tablets or pills. In certain embodiments, the solid oral dosage form further comprises buffering agents. In certain embodiments, such compositions for solid oral dosage forms may be formulated as fillers in soft and hard-filled gelatin capsules comprising one or more excipients such as lactose or milk sugar, polyethylene glycols and the like.

In certain embodiments, tablets, dragees, capsules, pills and granules of the compositions comprising a compound of formula I or salt thereof optionally comprise coatings or shells such as enteric coatings. They may optionally comprise opacifying agents and can also be of a composition that they release the active ingredient(s) only, or preferentially, in a certain part of the intestinal tract, optionally, in a delayed manner. Examples of embedding compositions include polymeric substances and waxes, which may also be employed as fillers in soft and hard-filled gelatin capsules using such excipients as lactose or milk sugar as well as high molecular weight polyethylene glycols and the like.

In another embodiment, a composition comprises micro-encapsulated compound of formula (I) or salt thereof, and optionally, further comprises one or more excipients.

In another embodiment, compositions comprise liquid dosage formulations comprising a compound of formula I or salt thereof for oral administration, and optionally further comprise one or more of pharmaceutically acceptable emulsions, microemulsions, solutions, suspensions, syrups and elixirs. In certain embodiments, the liquid dosage form optionally, further comprise one or more of an inert diluent such as water or other solvent, a solubilizing agent, and an emulsifier such as ethyl alcohol, isopropyl alcohol, ethyl carbonate, ethyl acetate, benzyl alcohol, benzyl benzoate, propylene glycol, 1,3-butylene glycol, dimethylformamide, oils (in particular, cottonseed, groundnut, corn, germ, olive, castor, and sesame oils), glycerol, tetrahydrofurfuryl alcohol, polyethylene glycols or fatty acid esters of sorbitan, and mixtures thereof. In certain embodiments, liquid oral compositions optionally further comprise one or more adjuvant, such as a wetting agent, a suspending agent, a sweetening agent, a flavoring agent and a perfuming agent.

Injectable preparations, for example, sterile injectable aqueous or oleaginous suspensions may be formulated according to the known art using suitable dispersing or wetting agents and suspending agents. The sterile injectable preparation may also be a sterile injectable solution, suspension or emulsion in a nontoxic parenterally acceptable diluent or solvent, for example, as a solution in 1,3-butanediol. Among the acceptable vehicles and solvents that may be employed are water, Ringer's solution, U.S.P. and isotonic sodium chloride solution. In addition, sterile, fixed oils are conventionally employed as a solvent or suspending medium. For this purpose any bland fixed oil can be employed including synthetic mono- or diglycerides. In addition, fatty acids such as oleic acid are used in the preparation of injectables.

Injectable formulations can be sterilized, for example, by filtration through a bacterial-retaining filter, or by incorporating sterilizing agents in the form of sterile solid compositions which can be dissolved or dispersed in sterile water or other sterile injectable medium prior to use.

In order to prolong the effect of a compound of formula (I), it is often desirable to slow the absorption of the compound from subcutaneous or intramuscular injection. This may be accomplished by the use of a liquid suspension of crystalline or amorphous material with poor water solubility. The rate of absorption of the compound then depends upon its rate of dissolution that, in turn, may depend upon crystal size and crystalline form. Alternatively, delayed absorption of a parenterally administered compound form is accomplished by dissolving or suspending the compound in an oil vehicle. Injectable depot forms are made by forming microencapsule matrices of the compound in biodegradable polymers such as polylactide-polyglycolide. Depending upon the ratio of compound to polymer and the nature of the particular polymer employed, the rate of compound release can be controlled. Examples of other biodegradable polymers include poly(orthoesters) and poly(anhydrides). Depot injectable formulations are also prepared by entrapping the compound in liposomes or microemulsions that are compatible with body tissues.

In certain embodiments, the composition for rectal or vaginal administration are formulated as suppositories which can be prepared by mixing a compound of formula (I) or a salt thereof with suitable non-irritating excipients or carriers such as cocoa butter, polyethylene glycol or a suppository wax, for example those which are solid at ambient temperature but liquid at body temperature and therefore melt in the rectum or vaginal cavity and release the compound of formula (I).

Example dosage forms for topical or transdermal administration of a compound of formula (I) include ointments, pastes, creams, lotions, gels, powders, solutions, sprays, inhalants or patches. The compound of formula (I) or a salt thereof is admixed under sterile conditions with a pharmaceutically acceptable carrier, and optionally preservatives or buffers. Additional formulation examples include an ophthalmic formulation, ear drops, eye drops, transdermal patches. Transdermal dosage forms can be made by dissolving or dispensing the compound of formula (I) or a salt thereof in medium, for example ethanol or dimethylsulfoxide. Absorption enhancers can also be used to increase the flux of the compound across the skin. The rate can be controlled by either providing a rate controlling membrane or by dispersing the compound in a polymer matrix or gel.

Nasal aerosol or inhalation formulations of a compound of formula (I) or a salt thereof may be prepared as solutions in saline, employing benzyl alcohol or other suitable preservatives, absorption promoters to enhance bioavailability, fluorocarbons, and/or other conventional solubilizing or dispersing agents.

In certain embodiments, pharmaceutical compositions may be administered with or without food. In certain embodiments, pharmaceutically acceptable compositions are administered without food. In certain embodiments, pharmaceutically acceptable compositions of this invention are administered with food.

Specific dosage and treatment regimen for any particular patient will depend upon a variety of factors, including age, body weight, general health, sex, diet, time of administration, rate of excretion, drug combination, the judgment of the treating physician, and the severity of the particular disease being treated. The amount of a provided compound of formula I or salt thereof in the composition will also depend upon the particular compound in the composition.

In one embodiment, the therapeutically effective amount of the compound of the invention administered parenterally per dose will be in the range of about 0.01-100 mg/kg, alternatively about 0.1 to 20 mg/kg of patient body weight per day, with the typical initial range of compound used being 0.3 to 15 mg/kg/day. In another embodiment, oral unit dosage forms, such as tablets and capsules, contain from about 5 to about 100 mg of the compound of the invention.

An example tablet oral dosage form comprises about 2 mg, 5 mg, 25 mg, 50 mg, 100 mg, 250 mg or 500 mg of a compound of formula (I) or salt thereof, and further comprises about 5-30 mg anhydrous lactose, about 5-40 mg sodium croscarmellose, about 5-30 mg polyvinylpyrrolidone (PVP) K30 and about 1-10 mg magnesium stearate. The process of formulating the tablet comprises mixing the powdered ingredients together and further mixing with a solution of the PVP. The resulting composition can be dried, granulated, mixed with the magnesium stearate and compressed to tablet form using conventional equipment. An example of an aerosol formulation can be prepared by dissolving about 2-500 mg of a compound of formula I or salt thereof, in a suitable buffer solution, e.g. a phosphate buffer, and adding a tonicifier, e.g. a salt such sodium chloride, if desired. The solution may be filtered, e.g. using a 0.2 micron filter, to remove impurities and contaminants.

Uses of Compounds and Pharmaceutically Acceptable Compositions

Another aspect includes the use of a compound of formula (I) or a salt thereof for the inhibition of a bromodomain of PCAF (in vitro or in vivo).

Another embodiment includes a method for treating a PCAF mediated disorder in an animal (e.g., a mammal such as a human) comprising administering a compound of formula (I), or a pharmaceutically acceptable salt thereof to the animal. PCAF mediated disorders include, but are not limited to those disorders described herein.

Another aspect includes the use of a compound of formula (I) or a salt thereof for the inhibition of a bromodomain of GCN5 (in vitro or in vivo).

Another embodiment includes a method for treating a GCN5 mediated disorder in an animal (e.g., a mammal such as a human) comprising administering a compound of formula (I), or a pharmaceutically acceptable salt thereof to the animal.

Another embodiment includes a method of increasing efficacy of a cancer treatment comprising a cytotoxic agent in an animal (e.g., a mammal such as a human) comprising administering to the animal an effective amount of a compound of formula (I) or a pharmaceutically acceptable salt thereof.

Another embodiment includes a method of delaying or preventing development of cancer resistance to a cytotoxic agent in an animal (e.g., a mammal such as a human), comprising administering to the animal a compound of formula (I) or a pharmaceutically acceptable salt thereof.

Another embodiment includes a method of extending the duration of response to a cancer therapy in an animal (e.g., a mammal such as a human), comprising administering to an animal undergoing the cancer therapy a compound of formula (I) or a pharmaceutically acceptable salt thereof, wherein the duration of response to the cancer therapy when the compound of formula (I) or the pharmaceutically acceptable salt thereof is administered is extended over the duration of response to the cancer therapy in the absence of the administration of the compound of formula (I) or the pharmaceutically acceptable salt thereof.

Another embodiment includes a method of treating cancer in an individual comprising administering to the individual (a) a compound of formula (I) or a pharmaceutically acceptable salt thereof, and (b) a cytotoxic agent. In one embodiment the cytotoxic agent is selected from anti-microtubule agents, platinum coordination complexes, alkylating agents, antibiotic agents, topoisomerase II inhibitors, antimetabolites, topoisomerase I inhibitors, hormones and hormonal analogues, signal transduction pathway inhibitors, non-receptor tyrosine kinase angiogenesis inhibitors, immunotherapeutic agents, proapoptotic agents, inhibitors of LDH-A, inhibitors of fatty acid biosynthesis, cell cycle signaling inhibitors, HDAC inhibitors, proteasome inhibitors, and inhibitors of cancer metabolism. In one embodiment the cytotoxic agent is a taxane. In one embodiment the taxane is paclitaxel or docetaxel. In one embodiment the cytotoxic agent is a platinum agent. In one embodiment the cytotoxic agent is an antagonist of EGFR. In one embodiment the antagonist of EGFR is N-(3-ethynylphenyl)-6,7-bis(2-methoxyethoxy)quinazolin-4-amine or a pharmaceutically acceptable salt thereof (e.g., erlotinib). In one embodiment the cytotoxic agent is a RAF inhibitor. In one embodiment the RAF inhibitor is a BRAF or CRAF inhibitor. In one embodiment the RAF inhibitor is vemurafenib. In one embodiment the cytotoxic agent is a PI3K inhibitor.

In certain embodiments, treatment may be administered after one or more symptoms have developed. In other embodiments, treatment may be administered in the absence of symptoms. For example, treatment may be administered to a susceptible individual prior to the onset of symptoms (e.g., in light of a history of symptoms and/or in light of genetic or other susceptibility factors). Treatment may also be continued after symptoms have resolved, for example to prevent or delay their recurrence.

PCAF Mediated Disorders

A “PCAF mediated disorder” is characterized by the participation of PCAF in the inception, manifestation of one or more symptoms or disease markers, severity, or progression of a disorder.

PCAF mediated disorders include cancers, including, but not limited to acoustic neuroma, acute leukemia, acute lymphocytic leukemia, acute myelocytic leukemia, acute T-cell leukemia, androgen-responsive prostate cancer, basal cell carcinoma, bile duct carcinoma, bladder cancer, brain cancer, breast cancer, bronchogenic carcinoma, cervical cancer, chondrosarcoma, chordoma, choriocarcinoma, chronic leukemia, chronic lymphocytic leukemia, chronic myelocytic leukemia, chronic myelogenous leukemia, colon cancer, colorectal cancer, craniopharyngioma, cystadenocarcinoma, diffuse large B-cell lymphoma, drug resistant breast cancer, dysproliferative changes, embryonal carcinoma, endometrial cancer, endotheliosarcoma, ependymoma, epithelial carcinoma, erythroleukemia, esophageal cancer, estrogen-receptor positive breast cancer, essential thrombocythemia, Ewing's tumor, fibrosarcoma, follicular lymphoma, gastric cancer, germ cell testicular cancer, glioma, glioblastoma, gliosarcoma, heavy chain disease, head and neck cancer, hemangioblastoma, hepatoma, hepatocellular cancer, hormone insensitive prostate cancer, leiomyosarcoma, leukemia, liposarcoma, lung cancer, lymphagioendotheliosarcoma, lymphangiosarcoma, lymphoblastic leukemia, lymphoma, lymphoid malignancies of T-cell or B-cell origin, medullary carcinoma, medulloblastoma, melanoma, meningioma, mesothelioma, multiple myeloma, myelogenous leukemia, myeloma, myxosarcoma, neuroblastoma, NUT midline carcinoma (NMC), non-small cell lung cancer, oligodendroglioma, oral cancer, osteogenic sarcoma, ovarian cancer, pancreatic cancer, papillary adenocarcinomas, papillary carcinoma, pediatric acute lymphoblastic leukemia, pinealoma, polycythemia vera, prostate cancer, rectal cancer, renal cell carcinoma, retinoblastoma, rhabdomyosarcoma, sarcoma, sebaceous gland carcinoma, seminoma, skin cancer, small cell lung carcinoma, solid tumors (carcinomas and sarcomas), small cell lung cancer, stomach cancer, squamous cell carcinoma, synovioma, sweat gland carcinoma, thyroid cancer, Waldenstrom's macroglobulinemia, wnt-dependent breast cancer, testicular tumors, uterine cancer, and Wilms' tumor.

In certain embodiments, the cancer is selected from the group consisting of gastric cancer, lung cancer, non-small cell lung cancer, pancreatic cancer, pediatric acute lymphoblastic leukemia, androgen-responsive prostate cancer, breast cancer, wnt-dependent breast cancer, drug-resistant breast cancer, estrogen-receptor positive breast cancer, leukemia, neuroblastoma, colon cancer, and cervical cancer. In certain embodiments, the cancer is lung cancer. In certain embodiments, the cancer is pancreatic cancer. In certain embodiments, the cancer is breast cancer. In certain embodiments, the cancer is leukemia. In certain embodiments, the cancer is colon cancer. In certain embodiments, the cancer is cervical cancer.

PCAF mediated disorders also include inflammatory diseases, inflammatory conditions, and autoimmune diseases, including, but not limited to: Addison's disease, acute gout, Alzheimer's disease (inflammatory-mediated neurotoxicity), ankylosing spondylitis, asthma, atherosclerosis, Behcet's disease, bullous skin diseases, chronic obstructive pulmonary disease (COPD), Crohn's disease, dermatitis, eczema, giant cell arteritis, glomerulonephritis, hepatitis, hypophysitis, inflammatory bowel disease, Kawasaki disease, lupus nephritis, multiple sclerosis, myocarditis, myositis, nephritis, organ transplant rejection, osteoarthritis, pancreatitis, pericarditis, Polyarteritis nodosa, pneumonitis, primary biliary cirrhosis, psoriasis, psoriatic arthritis, rheumatoid arthritis, scleritis, sclerosing cholangitis, sepsis, systemic lupus erythematosus, Takayasu's Arteritis, toxic shock, thyroiditis, type I diabetes, ulcerative colitis, uveitis, vitiligo, vasculitis, and Wegener's granulomatosis. In some embodiments, the disorder is an autoimmune disease. In some embodiments, the disorder is asthma.

PCAF mediated disorders also include AIDS; chronic kidney diseases, including, but are not limited to diabetic nephropathy, hypertensive nephropathy, HIV-associated nephropathy, glomerulonephritis, lupus nephritis, IgA nephropathy, focal segmental glomerulosclerosis, membranous glomerulonephritis, minimal change disease, polycystic kidney disease and tubular interstitial nephritis; acute kidney injury or disease or condition including, but are not limited to ischemia-reperfusion induced, cardiac and major surgery induced, percutaneous coronary intervention induced, radio-contrast agent induced, sepsis induced, pneumonia induced, and drug toxicity induced; HIV infection; obesity; osteoporosis, dyslipidemia; hypercholesterolemia; Alzheimer's disease; metabolic syndrome; hepatic steatosis; type II diabetes; insulin resistance; diabetic retinopathy; osteoporosis; obesity, and parasitic infection (e.g., Toxoplasma gondii). In some embodiments, the disorder is osteoporosis. In some embodiments, the disorder is obesity. In some embodiments, the disorder is HIV infection. In some embodiments, the disorder is parasitic infection.

GCN5 Mediated Disorders

A “GCN5 mediated disorder” is characterized by the participation of the GCN5 in the inception, manifestation of one or more symptoms or disease markers, severity, or progression of a disorder.

GCN5 mediated disorders include cancers, including, but not limited to acoustic neuroma, acute leukemia, acute lymphocytic leukemia, acute myelocytic leukemia, acute T-cell leukemia, androgen-responsive prostate cancer, basal cell carcinoma, bile duct carcinoma, bladder cancer, brain cancer, breast cancer, bronchogenic carcinoma, cervical cancer, chondrosarcoma, chordoma, choriocarcinoma, chronic leukemia, chronic lymphocytic leukemia, chronic myelocytic leukemia, chronic myelogenous leukemia, colon cancer, colorectal cancer, craniopharyngioma, cystadenocarcinoma, diffuse large B-cell lymphoma, drug resistant breast cancer, dysproliferative changes, embryonal carcinoma, endometrial cancer, endotheliosarcoma, ependymoma, epithelial carcinoma, erythroleukemia, esophageal cancer, estrogen-receptor positive breast cancer, essential thrombocythemia, Ewing's tumor, fibrosarcoma, follicular lymphoma, gastric cancer, germ cell testicular cancer, glioma, glioblastoma, gliosarcoma, heavy chain disease, head and neck cancer, hemangioblastoma, hepatoma, hepatocellular cancer, hormone insensitive prostate cancer, leiomyosarcoma, leukemia, liposarcoma, lung cancer, lymphagioendotheliosarcoma, lymphangiosarcoma, lymphoblastic leukemia, lymphoma, lymphoid malignancies of T-cell or B-cell origin, medullary carcinoma, medulloblastoma, melanoma, meningioma, mesothelioma, multiple myeloma, myelogenous leukemia, myeloma, myxosarcoma, neuroblastoma, NUT midline carcinoma (NMC), non-small cell lung cancer, oligodendroglioma, oral cancer, osteogenic sarcoma, ovarian cancer, pancreatic cancer, papillary adenocarcinomas, papillary carcinoma, pediatric acute lymphoblastic leukemia, pinealoma, polycythemia vera, prostate cancer, rectal cancer, renal cell carcinoma, retinoblastoma, rhabdomyosarcoma, sarcoma, sebaceous gland carcinoma, seminoma, skin cancer, small cell lung carcinoma, solid tumors (carcinomas and sarcomas), small cell lung cancer, stomach cancer, squamous cell carcinoma, synovioma, sweat gland carcinoma, thyroid cancer, Waldenstrom's macroglobulinemia, wnt-dependent breast cancer, testicular tumors, uterine cancer, and Wilms' tumor.

In certain embodiments, the cancer is selected from the group consisting of gastric cancer, lung cancer, non-small cell lung cancer, pancreatic cancer, pediatric acute lymphoblastic leukemia, androgen-responsive prostate cancer, breast cancer, wnt-dependent breast cancer, drug-resistant breast cancer, estrogen-receptor positive breast cancer, leukemia, neuroblastoma, colon cancer, and cervical cancer. In certain embodiments, the cancer is lung cancer. In certain embodiments, the cancer is pancreatic cancer. In certain embodiments, the cancer is breast cancer. In certain embodiments, the cancer is leukemia. In certain embodiments, the cancer is colon cancer. In certain embodiments, the cancer is cervical cancer.

GCN5 mediated disorders also include inflammatory diseases, inflammatory conditions, and autoimmune diseases, including, but not limited to: Addison's disease, acute gout, Alzheimer's disease (inflammatory-mediated neurotoxicity), ankylosing spondylitis, asthma, atherosclerosis, Behcet's disease, bullous skin diseases, chronic obstructive pulmonary disease (COPD), Crohn's disease, dermatitis, eczema, giant cell arteritis, glomerulonephritis, hepatitis, hypophysitis, inflammatory bowel disease, Kawasaki disease, lupus nephritis, multiple sclerosis, myocarditis, myositis, nephritis, organ transplant rejection, osteoarthritis, pancreatitis, pericarditis, Polyarteritis nodosa, pneumonitis, primary biliary cirrhosis, psoriasis, psoriatic arthritis, rheumatoid arthritis, scleritis, sclerosing cholangitis, sepsis, systemic lupus erythematosus, Takayasu's Arteritis, toxic shock, thyroiditis, type I diabetes, ulcerative colitis, uveitis, vitiligo, vasculitis, and Wegener's granulomatosis. In some embodiments, the disorder is an autoimmune disease. In some embodiments, the disorder is asthma.

GCN5 mediated disorders also include AIDS; chronic kidney diseases, including, but are not limited to diabetic nephropathy, hypertensive nephropathy, HIV-associated nephropathy, glomerulonephritis, lupus nephritis, IgA nephropathy, focal segmental glomerulosclerosis, membranous glomerulonephritis, minimal change disease, polycystic kidney disease and tubular interstitial nephritis; acute kidney injury or disease or condition including, but are not limited to ischemia-reperfusion induced, cardiac and major surgery induced, percutaneous coronary intervention induced, radio-contrast agent induced, sepsis induced, pneumonia induced, and drug toxicity induced; HIV infection; obesity; osteoporosis, dyslipidemia; hypercholesterolemia; Alzheimer's disease; metabolic syndrome; hepatic steatosis; type II diabetes; insulin resistance; diabetic retinopathy; osteoporosis; obesity, and parasitic infection (e.g., Toxoplasma gondii). In some embodiments, the disorder is osteoporosis. In some embodiments, the disorder is obesity. In some embodiments, the disorder is HIV infection. In some embodiments, the disorder is parasitic infection.

Co-Administration of Compounds and Other Agents

The compounds of formula (I) or salts thereof may be employed alone or in combination with other agents for treatment. For example, the second agent of the pharmaceutical combination formulation or dosing regimen may have complementary activities to the compound of formula (I) such that they do not adversely affect each other. The compounds may be administered together in a unitary pharmaceutical composition or separately. In one embodiment a compound or a pharmaceutically acceptable salt can be co-administered with a cytotoxic agent to treat proliferative diseases and cancer.

The term “co-administering” refers to either simultaneous administration, or any manner of separate sequential administration, of a compound of formula (I) or a salt thereof, and a further active pharmaceutical ingredient or ingredients, including cytotoxic agents and radiation treatment. If the administration is not simultaneous, the compounds are administered in a close time proximity to each other. Furthermore, it does not matter if the compounds are administered in the same dosage form, e.g. one compound may be administered topically and another compound may be administered orally.

Those additional agents may be administered separately from an inventive compound-containing composition, as part of a multiple dosage regimen. Alternatively, those agents may be part of a single dosage form, mixed together with a compound of this invention in a single composition. If administered as part of a multiple dosage regime, the two active agents may be submitted simultaneously, sequentially or within a period of time from one another normally within five hours from one another.

As used herein, the term “combination,” “combined,” and related terms refers to the simultaneous or sequential administration of therapeutic agents in accordance with this invention. For example, a compound of the present invention may be administered with another therapeutic agent simultaneously or sequentially in separate unit dosage forms or together in a single unit dosage form. Accordingly, the present invention provides a single unit dosage form comprising a compound of formula I, an additional therapeutic agent, and a pharmaceutically acceptable carrier, adjuvant, or vehicle.

The amount of both an inventive compound and additional therapeutic agent (in those compositions which comprise an additional therapeutic agent as described above) that may be combined with the carrier materials to produce a single dosage form will vary depending upon the host treated and the particular mode of administration. In certain embodiments, compositions of this invention are formulated such that a dosage of between 0.01-100 mg/kg body weight/day of an inventive can be administered.

Typically, any agent that has activity against a disease or condition being treated may be co-administered. Examples of such agents can be found in Cancer Principles and Practice of Oncology by V. T. Devita and S. Hellman (editors), 6^(th) edition (Feb. 15, 2001), Lippincott Williams & Wilkins Publishers. A person of ordinary skill in the art would be able to discern which combinations of agents would be useful based on the particular characteristics of the drugs and the disease involved.

In one embodiment, the treatment method includes the co-administration of a compound of formula (I) or a pharmaceutically acceptable salt thereof and at least one cytotoxic agent. The term “cytotoxic agent” as used herein refers to a substance that inhibits or prevents a cellular function and/or causes cell death or destruction. Cytotoxic agents include, but are not limited to, radioactive isotopes (e.g., At²¹, I¹³¹, I¹²⁵, Y⁹⁰, Re¹⁸⁶, Re¹⁸⁸, Sm¹⁵³, Bi²¹², P³², Pb²¹² and radioactive isotopes of Lu); chemotherapeutic agents; growth inhibitory agents; enzymes and fragments thereof such as nucleolytic enzymes; and toxins such as small molecule toxins or enzymatically active toxins of bacterial, fungal, plant or animal origin, including fragments and/or variants thereof.

Exemplary cytotoxic agents can be selected from anti-microtubule agents, platinum coordination complexes, alkylating agents, antibiotic agents, topoisomerase II inhibitors, antimetabolites, topoisomerase I inhibitors, hormones and hormonal analogues, signal transduction pathway inhibitors, non-receptor tyrosine kinase angiogenesis inhibitors, immunotherapeutic agents, proapoptotic agents, inhibitors of LDH-A; inhibitors of fatty acid biosynthesis; cell cycle signaling inhibitors; HDAC inhibitors, proteasome inhibitors; and inhibitors of cancer metabolism.

“Chemotherapeutic agent” includes chemical compounds useful in the treatment of cancer. Examples of chemotherapeutic agents include erlotinib (TARCEVA®, Genentech/OSI Pharm.), bortezomib (VELCADE®, Millennium Pharm.), disulfiram, epigallocatechin gallate, salinosporamide A, carfilzomib, 17-AAG (geldanamycin), radicicol, lactate dehydrogenase A (LDH-A), fulvestrant (FASLODEX®, AstraZeneca), sunitib (SUTENT®, Pfizer/Sugen), letrozole (FEMARA®, Novartis), imatinib mesylate (GLEEVEC®, Novartis), finasunate (VATALANIB®, Novartis), oxaliplatin (ELOXATIN®, Sanofi), 5-FU (5-fluorouracil), leucovorin, Rapamycin (Sirolimus, RAPAMUNE®, Wyeth), Lapatinib (TYKERB®, GSK572016, Glaxo Smith Kline), Lonafamib (SCH 66336), sorafenib (NEXAVAR®, Bayer Labs), gefitinib (IRESSA®, AstraZeneca), AG1478, alkylating agents such as thiotepa and CYTOXAN® cyclosphosphamide; alkyl sulfonates such as busulfan, improsulfan and piposulfan; aziridines such as benzodopa, carboquone, meturedopa, and uredopa; ethylenimines and methylamelamines including altretamine, triethylenemelamine, triethylenephosphoramide, triethylenethiophosphoramide and trimethylomelamine; acetogenins (especially bullatacin and bullatacinone); a camptothecin (including topotecan and irinotecan); bryostatin; callystatin; CC-1065 (including its adozelesin, carzelesin and bizelesin synthetic analogs); cryptophycins (particularly cryptophycin 1 and cryptophycin 8); adrenocorticosteroids (including prednisone and prednisolone); cyproterone acetate; 5α-reductases including finasteride and dutasteride); vorinostat, romidepsin, panobinostat, valproic acid, mocetinostat dolastatin; aldesleukin, talc duocarmycin (including the synthetic analogs, KW-2189 and CB1-TMI); eleutherobin; pancratistatin; a sarcodictyin; spongistatin; nitrogen mustards such as chlorambucil, chlomaphazine, chlorophosphamide, estramustine, ifosfamide, mechlorethamine, mechlorethamine oxide hydrochloride, melphalan, novembichin, phenesterine, prednimustine, trofosfamide, uracil mustard; nitrosoureas such as carmustine, chlorozotocin, fotemustine, lonustine, nimustine, and ranimnustine; antibiotics such as the enediyne antibiotics (e.g., calicheamicin, especially calicheamicin γ1I and calicheamicin ω1I (Angew Chem. Intl. Ed. Engl. 1994 33:183-186); dynemicin, including dynemicin A; bisphosphonates, such as clodronate; an esperamicin; as well as neocarzinostatin chromophore and related chromoprotein enediyne antibiotic chromophores), aclacinomysins, actinomycin, authramycin, azaserine, bleomycins, cactinomycin, carabicin, caminomycin, carzinophilin, chromomycinis, dactinomycin, daunorubicin, detorubicin, 6-diazo-5-oxo-L-norleucine, ADRIAMYCIN® (doxorubicin), morpholino-doxorubicin, cyanomorpholino-doxorubicin, 2-pyrrolino-doxorubicin and deoxydoxorubicin), epirubicin, esorubicin, idarubicin, marcellomycin, mitomycins such as mitomycin C, mycophenolic acid, nogalamycin, olivomycins, peplomycin, porfiromycin, puromycin, quelamycin, rodorubicin, streptonigrin, streptozocin, tubercidin, ubenimex, zinostatin, zorubicin; anti-metabolites such as methotrexate and 5-fluorouracil (5-FU); folic acid analogs such as denopterin, methotrexate, pteropterin, trimetrexate; purine analogs such as fludarabine, 6-mercaptopurine, thiamiprine, thioguanine; pyrimidine analogs such as ancitabine, azacitidine, 6-azauridine, carmofur, cytarabine, dideoxyuridine, doxifluridine, enocitabine, floxuridine; androgens such as calusterone, dromostanolone propionate, epitiostanol, mepitiostane, testolactone; anti-adrenals such as aminoglutethimide, mitotane, trilostane; folic acid replenisher such as frolinic acid; aceglatone; aldophosphamide glycoside; aminolevulinic acid; eniluracil; amsacrine; bestrabucil; bisantrene; edatraxate; defofamine; demecolcine; diaziquone; elfomithine; elliptinium acetate; an epothilone; etoglucid; gallium nitrate; hydroxyurea; lentinan; lonidainine; maytansinoids such as maytansine and ansamitocins; mitoguazone; mitoxantrone; mopidamnol; nitraerine; pentostatin; phenamet; pirarubicin; losoxantrone; podophyllinic acid; 2-ethylhydrazide; procarbazine; PSK® polysaccharide complex (JHS Natural Products, Eugene, Oreg.); razoxane; rhizoxin; sizofuran; spirogermanium; tenuazonic acid; triaziquone; 2,2′,2″-trichlorotriethylamine; trichothecenes (especially T-2 toxin, verracurin A, roridin A and anguidine); urethan; vindesine; dacarbazine; mannomustine; mitobronitol; mitolactol; pipobroman; gacytosine; arabinoside (“Ara-C”); cyclophosphamide; thiotepa; taxoids, e.g., TAXOL (paclitaxel; Bristol-Myers Squibb Oncology, Princeton, N.J.), ABRAXANE® (Cremophor-free), albumin-engineered nanoparticle formulations of paclitaxel (American Pharmaceutical Partners, Schaumberg, Ill.), and TAXOTERE® (docetaxel, doxetaxel; Sanofi-Aventis); chloranmbucil; GEMZAR® (gemcitabine); 6-thioguanine; mercaptopurine; methotrexate; platinum analogs such as cisplatin and carboplatin; vinblastine; etoposide (VP-16); ifosfamide; mitoxantrone; vincristine; NAVELBINE® (vinorelbine); novantrone; teniposide; edatrexate; daunomycin; aminopterin; capecitabine (XELODA®); ibandronate; CPT-11; topoisomerase inhibitor RFS 2000; difluoromethylomithine (DMFO); retinoids such as retinoic acid; and pharmaceutically acceptable salts, acids and derivatives of any of the above.

Chemotherapeutic agent also includes (i) anti-hormonal agents that act to regulate or inhibit hormone action on tumors such as anti-estrogens and selective estrogen receptor modulators (SERMs), including, for example, tamoxifen (including NOLVADEX®; tamoxifen citrate), raloxifene, droloxifene, iodoxyfene, 4-hydroxytamoxifen, trioxifene, keoxifene, LY117018, onapristone, and FARESTON® (toremifine citrate); (ii) aromatase inhibitors that inhibit the enzyme aromatase, which regulates estrogen production in the adrenal glands, such as, for example, 4(5)-imidazoles, aminoglutethimide, MEGASE® (megestrol acetate), AROMASIN® (exemestane; Pfizer), formestanie, fadrozole, RIVISOR® (vorozole), FEMARA® (letrozole; Novartis), and ARIMIDEX® (anastrozole; AstraZeneca); (iii) anti-androgens such as flutamide, nilutamide, bicalutamide, leuprolide and goserelin; buserelin, tripterelin, medroxyprogesterone acetate, diethylstilbestrol, premarin, fluoxymesterone, all transretionic acid, fenretinide, as well as troxacitabine (a 1,3-dioxolane nucleoside cytosine analog); (iv) protein kinase inhibitors; (v) lipid kinase inhibitors; (vi) antisense oligonucleotides, particularly those which inhibit expression of genes in signaling pathways implicated in aberrant cell proliferation, such as, for example, PKC-alpha, Ralf and H-Ras; (vii) ribozymes such as VEGF expression inhibitors (e.g., ANGIOZYME®) and HER2 expression inhibitors; (viii) vaccines such as gene therapy vaccines, for example, ALLOVECTIN®, LEUVECTIN®, and VAXID®; PROLEUKIN®, rIL-2; a topoisomerase I inhibitor such as LURTOTECAN®; ABARELIX® rmRH; and (ix) pharmaceutically acceptable salts, acids and derivatives of any of the above.

Chemotherapeutic agent also includes antibodies such as alemtuzumab (Campath), bevacizumab (AVASTIN®, Genentech); cetuximab (ERBITUX®, Imclone); panitumumab (VECTIBIX®, Amgen), rituximab (RITUXAN®, Genentech/Biogen Idec), pertuzumab (OMNITARG®, 2C4, Genentech), trastuzumab (HERCEPTIN®, Genentech), tositumomab (Bexxar, Corixia), and the antibody drug conjugate, gemtuzumab ozogamicin (MYLOTARG®, Wyeth). Additional humanized monoclonal antibodies with therapeutic potential as agents in combination with the compounds of the invention include: apolizumab, aselizumab, atlizumab, bapineuzumab, bivatuzumab mertansine, cantuzumab mertansine, cedelizumab, certolizumab pegol, cidfusituzumab, cidtuzumab, daclizumab, eculizumab, efalizumab, epratuzumab, erlizumab, felvizumab, fontolizumab, gemtuzumab ozogamicin, inotuzumab ozogamicin, ipilimumab, labetuzumab, lintuzumab, matuzumab, mepolizumab, motavizumab, motovizumab, natalizumab, nimotuzumab, nolovizumab, numavizumab, ocrelizumab, omalizumab, palivizumab, pascolizumab, pecfusituzumab, pectuzumab, pexelizumab, ralivizumab, ranibizumab, reslivizumab, reslizumab, resyvizumab, rovelizumab, ruplizumab, sibrotuzumab, siplizumab, sontuzumab, tacatuzumab tetraxetan, tadocizumab, talizumab, tefibazumab, tocilizumab, toralizumab, tucotuzumab celmoleukin, tucusituzumab, umavizumab, urtoxazumab, ustekinumab, visilizumab, and the anti-interleukin-12 (ABT-874/J695, Wyeth Research and Abbott Laboratories) which is a recombinant exclusively human-sequence, full-length IgG₁ λ antibody genetically modified to recognize interleukin-12 p40 protein.

Chemotherapeutic agent also includes “EGFR inhibitors,” which refers to compounds that bind to or otherwise interact directly with EGFR and prevent or reduce its signaling activity, and is alternatively referred to as an “EGFR antagonist.” Examples of such agents include antibodies and small molecules that bind to EGFR. Examples of antibodies which bind to EGFR include MAb 579 (ATCC CRL HB 8506), MAb 455 (ATCC CRL HB8507), MAb 225 (ATCC CRL 8508), MAb 528 (ATCC CRL 8509) (see, U.S. Pat. No. 4,943,533, Mendelsohn et al.) and variants thereof, such as chimerized 225 (C225 or Cetuximab; ERBUTIX®) and reshaped human 225 (H225) (see, WO 96/40210, Imclone Systems Inc.); IMC-11F8, a fully human, EGFR-targeted antibody (Imclone); antibodies that bind type II mutant EGFR (U.S. Pat. No. 5,212,290); humanized and chimeric antibodies that bind EGFR as described in U.S. Pat. No. 5,891,996; and human antibodies that bind EGFR, such as ABX-EGF or Panitumumab (see WO98/50433, Abgenix/Amgen); EMD 55900 (Stragliotto et al. Eur. J. Cancer 32A:636-640 (1996)); EMD7200 (matuzumab) a humanized EGFR antibody directed against EGFR that competes with both EGF and TGF-alpha for EGFR binding (EMD/Merck); human EGFR antibody, HuMax-EGFR (GenMab); fully human antibodies known as E1.1, E2.4, E2.5, E6.2, E6.4, E2.11, E6.3 and E7.6.3 and described in U.S. Pat. No. 6,235,883; MDX-447 (Medarex Inc); and mAb 806 or humanized mAb 806 (Johns et al., J. Biol. Chem. 279(29):30375-30384 (2004)). The anti-EGFR antibody may be conjugated with a cytotoxic agent, thus generating an immunoconjugate (see, e.g., EP659,439A2, Merck Patent GmbH). EGFR antagonists include small molecules such as compounds described in U.S. Pat. Nos. 5,616,582, 5,457,105, 5,475,001, 5,654,307, 5,679,683, 6,084,095, 6,265,410, 6,455,534, 6,521,620, 6,596,726, 6,713,484, 5,770,599, 6,140,332, 5,866,572, 6,399,602, 6,344,459, 6,602,863, 6,391,874, 6,344,455, 5,760,041, 6,002,008, and 5,747,498, as well as the following PCT publications: WO98/14451, WO98/50038, WO99/09016, and WO99/24037. Particular small molecule EGFR antagonists include OS1-774 (CP-358774, erlotinib, TARCEVA® Genentech/OSI Pharmaceuticals); PD 183805 (CI 1033, 2-propenamide, N-[4-[(3-chloro-4-fluorophenyl)amino]-7-[3-(4-morpholinyl)propoxy]-6-quinazolinyl]-, dihydrochloride, Pfizer Inc.); ZD1839, gefitinib (IRESSA®) 4-(3′-Chloro-4′-fluoroanilino)-7-methoxy-6-(3-morpholinopropoxy)quinazoline, AstraZeneca); ZM 105180 ((6-amino-4-(3-methylphenyl-amino)-quinazoline, Zeneca); BIBX-1382 (N8-(3-chloro-4-fluoro-phenyl)-N2-(1-methyl-piperidin-4-yl)-pyrimido[5,4-d]pyrimidine-2,8-diamine, Boehringer Ingelheim); PKI-166 ((R)-4-[4-[(1-phenylethyl)amino]-1H-pyrrolo[2,3-d]pyrimidin-6-yl]-phenol); (R)-6-(4-hydroxyphenyl)-4-[(1-phenylethyl)amino]-7H-pyrrolo[2,3-d]pyrimidine); CL-387785 (N-[4-[(3-bromophenyl)amino]-6-quinazolinyl]-2-butynamide); EKB-569 (N-[4-[(3-chloro-4-fluorophenyl)amino]-3-cyano-7-ethoxy-6-quinolinyl]-4-(dimethylamino)-2-butenamide) (Wyeth); AG1478 (Pfizer); AG1571 (SU 5271; Pfizer); dual EGFR/HER2 tyrosine kinase inhibitors such as lapatinib (TYKERB®, GSK572016 or N-[3-chloro-4-[(3 fluorophenyl)methoxy]phenyl]-6[5 [[[2methylsulfonyl)ethyl]amino]methyl]-2-furanyl]-4-quinazolinamine).

Chemotherapeutic agents also include “tyrosine kinase inhibitors” including the EGFR-targeted drugs noted in the preceding paragraph; small molecule HER2 tyrosine kinase inhibitor such as TAK165 available from Takeda; CP-724,714, an oral selective inhibitor of the ErbB2 receptor tyrosine kinase (Pfizer and OSI); dual-HER inhibitors such as EKB-569 (available from Wyeth) which preferentially binds EGFR but inhibits both HER2 and EGFR-overexpressing cells; lapatinib (GSK572016; available from Glaxo-SmithKline), an oral HER2 and EGFR tyrosine kinase inhibitor; PKI-166 (available from Novartis); pan-HER inhibitors such as canertinib (CI-1033; Pharmacia); Raf-1 inhibitors such as antisense agent ISIS-5132 available from ISIS Pharmaceuticals which inhibit Raf-1 signaling; non-HER targeted TK inhibitors such as imatinib mesylate (GLEEVEC®, available from Glaxo SmithKline); multi-targeted tyrosine kinase inhibitors such as sunitinib (SUTENT®, available from Pfizer); VEGF receptor tyrosine kinase inhibitors such as vatalanib (PTK787/ZK222584, available from Novartis/Schering AG); MAPK extracellular regulated kinase I inhibitor CI-1040 (available from Pharmacia); quinazolines, such as PD 153035,4-(3-chloroanilino) quinazoline; pyridopyrimidines; pyrimidopyrimidines; pyrrolopyrimidines, such as CGP 59326, CGP 60261 and CGP 62706; pyrazolopyrimidines, 4-(phenylamino)-7H-pyrrolo[2,3-d] pyrimidines; curcumin (diferuloyl methane, 4,5-bis (4-fluoroanilino)phthalimide); tyrphostines containing nitrothiophene moieties; PD-0183805 (Wamer-Lamber); antisense molecules (e.g. those that bind to HER-encoding nucleic acid); quinoxalines (U.S. Pat. No. 5,804,396); tryphostins (U.S. Pat. No. 5,804,396); ZD6474 (Astra Zeneca); PTK-787 (Novartis/Schering AG); pan-HER inhibitors such as CI-1033 (Pfizer); Affinitac (ISIS 3521; Isis/Lilly); imatinib mesylate (GLEEVEC®); PKI 166 (Novartis); GW2016 (Glaxo SmithKline); CI-1033 (Pfizer); EKB-569 (Wyeth); Semaxinib (Pfizer); ZD6474 (AstraZeneca); PTK-787 (Novartis/Schering AG); INC-1C11 (lmclone), rapamycin (sirolimus, RAPAMUNE®); or as described in any of the following patent publications: U.S. Pat. No. 5,804,396; WO 1999/09016 (American Cyanamid); WO 1998/43960 (American Cyanamid); WO 1997/38983 (Warner Lambert); WO 1999/06378 (Warner Lambert); WO 1999/06396 (Warner Lambert); WO 1996/30347 (Pfizer, Inc); WO 1996/33978 (Zeneca); WO 1996/3397 (Zeneca) and WO 1996/33980 (Zeneca).

Chemotherapeutic agents also include dexamethasone, interferons, colchicine, metoprine, cyclosporine, amphotericin, metronidazole, alemtuzumab, alitretinoin, allopurinol, amifostine, arsenic trioxide, asparaginase, BCG live, bevacuzimab, bexarotene, cladribine, clofarabine, darbepoetin alfa, denileukin, dexrazoxane, epoetin alfa, elotinib, filgrastim, histrelin acetate, ibritumomab, interferon alfa-2a, interferon alfa-2b, lenalidomide, levamisole, mesna, methoxsalen, nandrolone, nelarabine, nofetumomab, oprelvekin, palifermin, pamidronate, pegademase, pegaspargase, pegfilgrastim, pemetrexed disodium, plicamycin, porfimer sodium, quinacrine, rasburicase, sargramostim, temozolomide, VM-26, 6-TG, toremifene, tretinoin, ATRA, valrubicin, zoledronate, and zoledronic acid, and pharmaceutically acceptable salts thereof.

Chemotherapeutic agents also include hydrocortisone, hydrocortisone acetate, cortisone acetate, tixocortol pivalate, triamcinolone acetonide, triamcinolone alcohol, mometasone, amcinonide, budesonide, desonide, fluocinonide, fluocinolone acetonide, betamethasone, betamethasone sodium phosphate, dexamethasone, dexamethasone sodium phosphate, fluocortolone, hydrocortisone-17-butyrate, hydrocortisone-17-valerate, aclometasone dipropionate, betamethasone valerate, betamethasone dipropionate, prednicarbate, clobetasone-17-butyrate, clobetasol-17-propionate, fluocortolone caproate, fluocortolone pivalate and fluprednidene acetate; immune selective anti-inflammatory peptides (ImSAIDs) such as phenylalanine-glutamine-glycine (FEG) and its D-isomeric form (feG) (IMULAN BioTherapeutics, LLC); anti-rheumatic drugs such as azathioprine, ciclosporin (cyclosporine A), D-penicillamine, gold salts, hydroxychloroquine, leflunomideminocycline, sulfasalazine, tumor necrosis factor alpha (TNFα) blockers such as etanercept (Enbrel), infliximab (Remicade), adalimumab (Humira), certolizumab pegol (Cimzia), golimumab (Simponi), Interleukin 1 (IL-1) blockers such as anakinra (Kineret), T cell costimulation blockers such as abatacept (Orencia), Interleukin 6 (IL-6) blockers such as tocilizumab (ACTEMERA®); Interleukin 13 (IL-13) blockers such as lebrikizumab; Interferon alpha (IFN) blockers such as Rontalizumab; Beta 7 integrin blockers such as rhuMAb Beta7; IgE pathway blockers such as Anti-Mi prime; Secreted homotrimeric LTa3 and membrane bound heterotrimer LTal/2 blockers such as Anti-lymphotoxin alpha (LTa); radioactive isotopes (e.g., At²¹¹, I¹³¹, I¹²⁵, Y⁹⁰, Re¹⁸⁶, Re¹⁸⁸, Sm¹⁵³, Bi²¹², P³², Pb²¹² and radioactive isotopes of Lu); miscellaneous investigational agents such as thioplatin, PS-341, phenylbutyrate, ET-18-OCH₃, or farnesyl transferase inhibitors (L-739749, L-744832); polyphenols such as quercetin, resveratrol, piceatannol, epigallocatechine gallate, theaflavins, flavanols, procyanidins, betulinic acid and derivatives thereof; autophagy inhibitors such as chloroquine; delta-9-tetrahydrocannabinol (dronabinol, MARINOL®); beta-lapachone; lapachol; colchicines; betulinic acid; acetylcamptothecin, scopolectin, and 9-aminocamptothecin); podophyllotoxin; tegafur (UFTORAL®); bexarotene (TARGRETIN®); bisphosphonates such as clodronate (for example, BONEFOS® or OSTAC®), etidronate (DIDROCAL®), NE-58095, zoledronic acid/zoledronate (ZOMETA®), alendronate (FOSAMAX®), pamidronate (AREDIA®), tiludronate (SKELID®), or risedronate (ACTONEL®); and epidermal growth factor receptor (EGF-R); vaccines such as THERATOPE® vaccine; perifosine, COX-2 inhibitor (e.g. celecoxib or etoricoxib), proteosome inhibitor (e.g. PS341); CCI-779; tipifarnib (R11577); orafenib, ABT510; Bcl-2 inhibitor such as oblimersen sodium (GENASENSE®); pixantrone; farnesyltransferase inhibitors such as lonafarnib (SCH 6636, SARASAR™); and pharmaceutically acceptable salts, acids or derivatives of any of the above; as well as combinations of two or more of the above such as CHOP, an abbreviation for a combined therapy of cyclophosphamide, doxorubicin, vincristine, and prednisolone; and FOLFOX, an abbreviation for a treatment regimen with oxaliplatin (ELOXATIN™) combined with 5-FU and leucovorin.

Chemotherapeutic agents also include non-steroidal anti-inflammatory drugs with analgesic, antipyretic and anti-inflammatory effects. NSAIDs include non-selective inhibitors of the enzyme cyclooxygenase. Specific examples of NSAIDs include aspirin, propionic acid derivatives such as ibuprofen, fenoprofen, ketoprofen, flurbiprofen, oxaprozin and naproxen, acetic acid derivatives such as indomethacin, sulindac, etodolac, diclofenac, enolic acid derivatives such as piroxicam, meloxicam, tenoxicam, droxicam, lornoxicam and isoxicam, fenamic acid derivatives such as mefenamic acid, meclofenamic acid, flufenamic acid, tolfenamic acid, and COX-2 inhibitors such as celecoxib, etoricoxib, lumiracoxib, parecoxib, rofecoxib, rofecoxib, and valdecoxib. NSAIDs can be indicated for the symptomatic relief of conditions such as rheumatoid arthritis, osteoarthritis, inflammatory arthropathies, ankylosing spondylitis, psoriatic arthritis, Reiter's syndrome, acute gout, dysmenorrhoea, metastatic bone pain, headache and migraine, postoperative pain, mild-to-moderate pain due to inflammation and tissue injury, pyrexia, ileus, and renal colic.

In certain embodiments, chemotherapeutic agents include, but are not limited to, doxorubicin, dexamethasone, vincristine, cyclophosphamide, fluorouracil, topotecan, interferons, platinum derivatives, taxanes (e.g., paclitaxel, docetaxel), vinca alkaloids (e.g., vinblastine), anthracyclines (e.g., doxorubicin), epipodophyllotoxins (e.g., etoposide), cisplatin, an mTOR inhibitor (e.g., a rapamycin), methotrexate, actinomycin D, dolastatin 10, colchicine, trimetrexate, metoprine, cyclosporine, daunorubicin, teniposide, amphotericin, alkylating agents (e.g., chlorambucil), 5-fluorouracil, campthothecin, cisplatin, metronidazole, and imatinib mesylate, among others. In other embodiments, a compound of the present invention is administered in combination with a biologic agent, such as bevacizumab or panitumumab.

In certain embodiments, compounds of the present invention, or a pharmaceutically acceptable composition thereof, are administered in combination with an antiproliferative or chemotherapeutic agent selected from any one or more of abarelix, aldesleukin, alemtuzumab, alitretinoin, allopurinol, altretamine, amifostine, anastrozole, arsenic trioxide, asparaginase, azacitidine, BCG live, bevacuzimab, fluorouracil, bexarotene, bleomycin, bortezomib, busulfan, calusterone, capecitabine, camptothecin, carboplatin, carmustine, cetuximab, chlorambucil, cladribine, clofarabine, cyclophosphamide, cytarabine, dactinomycin, darbepoetin alfa, daunorubicin, denileukin, dexrazoxane, docetaxel, doxorubicin (neutral), doxorubicin hydrochloride, dromostanolone propionate, epirubicin, epoetin alfa, elotinib, estramustine, etoposide phosphate, etoposide, exemestane, filgrastim, floxuridine, fludarabine, fulvestrant, gefitinib, gemcitabine, gemtuzumab, goserelin acetate, histrelin acetate, hydroxyurea, ibritumomab, idarubicin, ifosfamide, imatinib mesylate, interferon alfa-2a, interferon alfa-2b, irinotecan, lenalidomide, letrozole, leucovorin, leuprolide acetate, levamisole, lomustine, megestrol acetate, melphalan, mercaptopurine, 6-MP, mesna, methotrexate, methoxsalen, mitomycin C, mitotane, mitoxantrone, nandrolone, nelarabine, nofetumomab, oprelvekin, oxaliplatin, paclitaxel, palifermin, pamidronate, pegademase, pegaspargase, pegfilgrastim, pemetrexed disodium, pentostatin, pipobroman, plicamycin, porfimer sodium, procarbazine, quinacrine, rasburicase, rituximab, sargramostim, sorafenib, streptozocin, sunitinib maleate, talc, tamoxifen, temozolomide, teniposide, VM-26, testolactone, thioguanine, 6-TG, thiotepa, topotecan, toremifene, tositumomab, trastuzumab, tretinoin, ATRA, uracil mustard, valrubicin, vinblastine, vincristine, vinorelbine, zoledronate, or zoledronic acid.

Chemotherapeutic agents also include treatments for Alzheimer's Disease such as donepezil hydrochloride and rivastigmine; treatments for Parkinson's Disease such as L-DOPA/carbidopa, entacapone, ropinrole, pramipexole, bromocriptine, pergolide, trihexephendyl, and amantadine; agents for treating multiple sclerosis (MS) such as beta interferon (e.g., Avonex® and Rebif®), glatiramer acetate, and mitoxantrone; treatments for asthma such as albuterol and montelukast sodium; agents for treating schizophrenia such as zyprexa, risperdal, seroquel, and haloperidol; anti-inflammatory agents such as corticosteroids, TNF blockers, IL-1 RA, azathioprine, cyclophosphamide, and sulfasalazine; immunomodulatory and immunosuppressive agents such as cyclosporin, tacrolimus, rapamycin, mycophenolate mofetil, interferons, corticosteroids, cyclophophamide, azathioprine, and sulfasalazine; neurotrophic factors such as acetylcholinesterase inhibitors, MAO inhibitors, interferons, anti-convulsants, ion channel blockers, riluzole, and anti-Parkinsonian agents; agents for treating cardiovascular disease such as beta-blockers, ACE inhibitors, diuretics, nitrates, calcium channel blockers, and statins; agents for treating liver disease such as corticosteroids, cholestyramine, interferons, and anti-viral agents; agents for treating blood disorders such as corticosteroids, anti-leukemic agents, and growth factors; and agents for treating immunodeficiency disorders such as gamma globulin.

Additionally, chemotherapeutic agents include pharmaceutically acceptable salts, acids or derivatives of any of chemotherapeutic agents, described herein, as well as combinations of two or more of them.

For treating an inflammatory disease or an autoimmune disease, a compound of formula (I) or a pharmaceutically acceptable salt thereof may be co-administered with methotrexate, tofacitinib, 6-mercaptopurine, azathioprine sulphasalazine, mesalazine, olsalazine chloroquinine/hydroxychloroquinine, penicillamine, aurothiomalate (intramuscular and oral), azathioprine, cochicine, corticosteroids (oral, inhaled, and local injection), a beta-2 adrenoreceptor agonist (salbutamol, terbutaline, salmeteral), a xanthine (theophylline, aminophylline), cromoglycate, nedocromil, ketotifen, ipratropium and oxitropium, cyclosporin, FK506, rapamycin, mycophenolate mofetil, leflunomide, an NSAID (e.g. ibuprofen), a corticosteroid (e. g. prednisolone), a phosphodiesterase inhibitor, an adensosine agonist, an antithrombotic agent, a complement inhibitor, an adrenergic agent, an agent that interferes with signalling by proinflammatory cytokines such as TNF or IL-1 (e.g., a NIK, IKK, p38 or MAP kinase inhibitor), an IL-1 converting enzyme inhibitor, a T-cell signalling inhibitor (e.g. a kinase inhibitor), a metalloproteinase inhibitor, sulfasalazine, a 6-mercaptopurine, an angiotensin converting enzyme inhibitor, a soluble cytokine receptor (e.g. soluble p55 or p75 TNF receptors and the derivatives p75TNFRigG (etanercept) and p55TNFRigG (Lenercept), siL-IRI, siL-IRII, siL-6R), an antiinflammatory cytokine (e.g. IL-4, IL-10, IL-11, IL-13 and TGF), celecoxib, folic acid, hydroxychloroquine sulfate, rofecoxib, etanercept, infliximab, adalimumab, certolizumab, tocilizumab, abatacept, naproxen, valdecoxib, sulfasalazine, methylprednisolone, meloxicam, methylprednisolone acetate, gold sodium thiomalate, aspirin, triamcinolone acetonide, propoxyphene napsylate/apap, folate, nabumetone, diclofenac, piroxicam, etodolac, diclofenac sodium, oxaprozin, oxycodone HCl, hydrocodone bitartrate/apap, diclofenac sodium/misoprostol, fentanyl, anakinra, tramadol HCl, salsalate, sulindac, cyanocobalamin/fa/pyridoxine, acetaminophen, alendronate sodium, prednisolone, cortisone, betamethasone, morphine sulfate, lidocaine hydrochloride, indomethacin, glucosamine sulf/chondroitin, amitriptyline HCl, sulfadiazine, oxycodone HCVacetaminophen, olopatadine HCl misoprostol, naproxen sodium, omeprazole, cyclophosphamide, rituximab, IL-1 TRAP, MRA, CTLA4-IG, IL-18 BP, anti-IL-12, Anti-ILIS, BIRB-796, SCIO-469, VX-702, AMG-548, VX-740, Roflumilast, IC-485, CDC-801, SIPI agonists (such as FTY720), a PKC family inhibitor (e.g. Ruboxistaurin or AEB-071) or Mesopram. In certain embodiments, a compound of formula (I) or a pharmaceutically acceptable salt thereof may be co-administered with methotrexate or leflunomide. In moderate or severe Rheumatoid arthritis cases, a compound of formula (I) or a pharmaceutically acceptable salt thereof may be co-administered with cyclosporine and anti-TNF antibodies as noted above. A compound of formula (I) or a pharmaceutically acceptable salt thereof may also be co-administered with: budenoside; epidermal growth factor; a corticosteroid; cyclosporin, sulfasalazine; an aminosalicylate; 6-mercaptopurine; azathioprine; metronidazole; a lipoxygenase inhibitor; mesalamine; olsalazine; balsalazide; an antioxidant; a thromboxane inhibitor; an IL-1 receptor antagonist; an anti-IL-1 monoclonal antibody; an anti-IL-6 monoclonal antibody; a growth factor; an elastase inhibitor; a pyridinyl-imidazole compound; an antibody to or antagonist of other human cytokines or growth factors (e.g. TNF, LT, IL-1, IL-2, IL-6, IL-7, IL-8, IL-12, IL-15, IL-16, IL-23, EMAP-II, GM-CSF, FGF, and PDGF); a cell surface molecule (e.g. CD2, CD3, CD4, CD8, CD25, CD28, CD30, CD40, CD45, CD69, or CD90 or their ligands); methotrexate; cyclosporine; FK506; rapamycin; mycophenolate mofetil; leflunomide; an NSAID (e.g. ibuprofen); a corticosteroid (e.g. prednisolone); a phosphodiesterase inhibitor; an adenosine agonist; an antithrombotic agent; a complement inhibitor; an adrenergic agent; an agent that interferes with signalling by proinflammatory cytokines such as TNF 5 or IL-1 (e.g. a NIK, IKK, or MAP kinase inhibitor); an IL-1 converting enzyme inhibitor; a TNF converting enzyme inhibitor; a T-cell signalling inhibitor such as kinase inhibitors; a metalloproteinase inhibitor; sulfasalazine; azathioprine; a 6-mercaptopurine; an angiotensin converting enzyme inhibitor; a soluble cytokine receptor (e.g. soluble p55 or p75 TNF receptors, siL-IRI, siL-IRII, siL-6R), and an antiinflammatory cytokine (e.g. IL-4, IL-10, IL-11, IL-13 or TGF).

For treating Crohn's disease, a compound of formula (I) or a pharmaceutically acceptable salt thereof may be co-administered with a TNF antagonist (e.g. an anti-TNF antibody), D2E7 (adalimumab), CA2 (infliximab), CDP 571, a TNFR-Ig construct, (p75TNFRigG (etanercept)), a p55TNFRigG (LENERCEPT™) inhibitor, or a PDE4 inhibitor.

For treating inflammatory bowel disease, a compound of formula (I) or a pharmaceutically acceptable salt thereof may be co-administered with a corticosteroid (e.g. budenoside or dexamethasone); sulfasalazine, 5-aminosalicylic acid; olsalazine; an agent that interferes with synthesis or action of proinflammatory cytokines such as IL-1 (e.g. an IL-1 converting enzyme inhibitor or IL-1ra); a T cell signaling inhibitor (e.g. a tyrosine kinase inhibitor); 6-mercaptopurine; IL-11; mesalamine; prednisone; azathioprine; mercaptopurine; infliximab; methylprednisolone sodium succinate; diphenoxylate/atrop sulfate; loperamide hydrochloride; methotrexate; omeprazole; folate; ciprofloxacin/dextrose-water; hydrocodone bitartrate/apap; tetracycline hydrochloride; fluocinonide; metronidazole; thimerosal/boric acid; cholestyramine/sucrose; ciprofloxacin hydrochloride; hyoscyamine sulfate; meperidine hydrochloride; midazolam hydrochloride; oxycodone HCl/acetaminophen; promethazine hydrochloride; sodium phosphate; sulfamethoxazole/trimethoprim; celecoxib; polycarbophil; propoxyphene napsylate; hydrocortisone; multivitamins; balsalazide disodium; codeine phosphate/apap; colesevelam HCl; cyanocobalamin; folic acid; levofloxacin; methylprednisolone; natalizumab or interferon-gamma.

For treating multiple sclerosis, a compound of formula (I) or a pharmaceutically acceptable salt thereof may be co-administered with a corticosteroid; prednisolone; methylprednisolone; azathioprine; cyclophosphamide; cyclosporine; methotrexate; 4-aminopyridine; tizanidine; interferon-1a (AVONEX®; Biogen); interferon-1b (BETASERON®; Chiron/Berlex); interferon-n3) (Interferon Sciences/Fujimoto), interferon-(Alfa Wassermann/J&J), interferon IA-IF (Serono/Inhale Therapeutics), Peginterferon 2b (Enzon/Schering-Plough), Copolymer 1 (Cop-1; COPAXONE®; Teva Pharmaceutical Industries, Inc.); hyperbaric oxygen; intravenous immunoglobulin; cladribine; an antibody to or antagonist of other human cytokines or growth factors and their receptors (e.g. TNF, LT, IL-1, IL-2, IL-6, IL-7, IL-8, IL-12, IL-23, IL-15, IL-16, EMAP-II, GM-CSF, FGF, or PDGF).

For treating AIDS a compound of formula (I) or a pharmaceutically acceptable salt thereof may be co-administered with antibodies to cell surface molecules such as CD2, CD3, CD4, CD8, CD19, CD20, CD25, CD28, CD30, CD40, CD45, CD69, CD80, CD86, CD90 or their ligands. A compound of Formula (I) or a pharmaceutically acceptable salt thereof may also be co-administered with methotrexate, cyclosporine, FK506, rapamycin, mycophenolate mofetil, leflunomide, an SlP1 agonist, an NSAID (e.g. ibuprofen), a corticosteroid (e.g. prednisolone), a phosphodiesterase inhibitor, an adensosine agonist, an antithrombotic agent, a complement inhibitor, an adrenergic agent, an agent that interferes with signalling by proinflammatory cytokines such as TNF or IL-1 (e.g., a NIK, IKK, p38 or MAP kinase inhibitor), an IL-1 converting enzyme inhibitor, a TACE inhibitor, a T-cell signaling inhibitor (e. g. a kinase inhibitor), a metalloproteinase inhibitor, sulfasalazine, azathioprine, a 6-mercaptopurine, an angiotensin converting enzyme inhibitor, a soluble cytokine receptor (e. g. soluble p55 or p75 TNF receptors, siL-IRI, siL-RII, or siL-6R), or an antiinflammatory cytokine (e.g. IL-4, IL-10, IL-13 or TGF).

A compound of formula (I) or a pharmaceutically acceptable salt thereof may also be co-administered with agents, such as alemtuzumab, dronabinol, daclizumab, mitoxantrone, xaliproden hydrochloride, fampridine, glatiramer acetate, natalizumab, sinnabidol, immunokine NNSO3, ABR-215062, AnergiX.MS, chemokine receptor antagonists, BBR-2778, calagualine, CPI-1189, LEM (liposome encapsulated mitoxantrone), THC.CBD (cannabinoid agonist), MBP-8298, mesopram (PDE4 inhibitor), MNA-715, an anti-IL-6 receptor antibody, neurovax, pirfenidone allotrap 1258 (RDP-1258), sTNF-R1, talampanel, teriflunomide, TGF-beta2, tiplimotide, a VLA-4 antagonist (e.g. TR-14035, VLA4 Ultrahaler, or Antegran-ELAN/Biogen), an interferon gamma antagonist, or an IL-4 agonist.

For treating ankylosing spondylitis a compound of formula (I) or a pharmaceutically acceptable salt thereof may be co-administered with ibuprofen, diclofenac, misoprostol, naproxen, meloxicam, indomethacin, diclofenac, celecoxib, rofecoxib, sulfasalazine, methotrexate, azathioprine, minocyclin, prednisone, an anti-TNF antibody, D2E7 (HUMIRA®), CA2 (infliximab), CDP 571, a TNFR-Ig construct, (p75TNFRigG (ENBREL®), or p55TNFRigG (LENERCEPT®).

For treating asthma a compound of formula (I) or a pharmaceutically acceptable salt thereof may be co-administered with albuterol, salmeterol/fluticasone, montelukast sodium, fluticasone propionate, budesonide, prednisone, salmeterol xinafoate, levalbuterol HCl, albuterol sulfate/ipratropium, prednisolone sodium phosphate, triamcinolone acetonide, beclomethasone dipropionate, ipratropium bromide, azithromycin, pirbuterol acetate, prednisolone, theophylline anhydrous, methylprednisolone sodium succinate, clarithromycin, zafirlukast, formoterol fumarate, influenza virus vaccine, amoxicillin trihydrate, flunisolide, cromolyn sodium, fexofenadine hydrochloride, flunisolide/menthol, amoxicillin/clavulanate, levofloxacin, guaifenesin, dexamethasone sodium phosphate, moxifloxacin HCl, doxycycline hyclate, guaifenesin/d-methorphan, p-ephedrine/cod/-chlorphenir, gatifloxacin, cetirizine hydrochloride, mometasone furoate, salmeterol xinafoate, benzonatate, cephalexin, pe/hydrocodone/chlorphenir, cetirizine HCl/pseudoephed, phenylephrine/cod/promethazine, codeine/promethazine, cefprozil, dexamethasone, guaifenesin/pseudoephedrine, chlorpheniramine/hydrocodone, nedocromil sodium, terbutaline sulfate, epinephrine, methylprednisolone, an anti-IL-13 antibody, or metaproterenol sulfate.

For treating COPD a compound of formula (I) or a pharmaceutically acceptable salt thereof may be co-administered with albuterol sulfate/ipratropium, ipratropium bromide, salmeterol/fluticasone, albuterol, salmeterol xinafoate, fluticasone propionate, prednisone, theophylline anhydrous, methylprednisolone sodium succinate, montelukast sodium, budesonide, formoterol fumarate, triamcinolone acetonide, levofloxacin, guaifenesin, azithromycin, beclomethasone dipropionate, levalbuterol HCl, flunisolide, ceftriaxone sodium, amoxicillin trihydrate, gatifloxacin, zafirlukast, amoxicillin/clavulanate, flunisolide/menthol, chlorpheniramine/hydrocodone, metaproterenol sulfate, methylprednisolone, mometasone furoate, p-ephedrine/cod/chlorphenir, pirbuterol acetate, p-ephedrine/loratadine, terbutaline sulfate, tiotropium bromide, (R,R)-formoterol, TgAAT, cilomilast, or roflumilast.

For treating psoriasis, a compound of formula (I) or a pharmaceutically acceptable salt thereof may be co-administered with calcipotriene, clobetasol propionate, triamcinolone acetonide, halobetasol propionate, tazarotene, methotrexate, fluocinonide, betamethasone diprop augmented, fluocinolone acetonide, acitretin, tar shampoo, betamethasone valerate, mometasone furoate, ketoconazole, pramoxine/fluocinolone, hydrocortisone valerate, flurandrenolide, urea, betamethasone, clobetasol propionate/emoll, fluticasone propionate, azithromycin, hydrocortisone, moisturizing formula, folic acid, desonide, pimecrolimus, coal tar, diflorasone diacetate, etanercept folate, lactic acid, methoxsalen, he/bismuth subgal/znox/resor, methylprednisolone acetate, prednisone, sunscreen, halcinonide, salicylic acid, anthralin, clocortolone pivalate, coal extract, coal tar/salicylic acid, coal tar/salicylic acid/sulfur, desoximetasone, diazepam, emollient, fluocinonide/emollient, mineral oil/castor oil/na lact, mineral oil/peanut oil, petroleum/isopropyl myristate, psoralen, salicylic acid, soap/tribromsalan, thimerosal/boric acid, celecoxib, infliximab, cyclosporine, alefacept, efalizumab, tacrolimus, pimecrolimus, PUVA, UVB, sulfasalazine, ABT-874 or ustekinamab.

For treating psoriatic arthritis, a compound of formula (I) or a pharmaceutically acceptable salt thereof may be co-administered with methotrexate, etanercept, rofecoxib, celecoxib, folic acid, sulfasalazine, naproxen, leflunomide, methylprednisolone acetate, indomethacin, hydroxychloroquine sulfate, prednisone, sulindac, betamethasone diprop augmented, infliximab, methotrexate, folate, triamcinolone acetonide, diclofenac, dimethylsulfoxide, piroxicam, diclofenac sodium, ketoprofen, meloxicam, methylprednisolone, nabumetone, tolmetin sodium, calcipotriene, cyclosporine, diclofenac sodium/misoprostol, fluocinonide, glucosamine sulfate, gold sodium thiomalate, hydrocodone bitartrate/apap, ibuprofen, risedronate sodium, sulfadiazine, thioguanine, valdecoxib, alefacept, D2E7 (adalimumab), or efalizumab.

For treating lupus, a compound of formula (I) or a pharmaceutically acceptable salt thereof may be co-administered with an NSAID (e.g. diclofenac, naproxen, ibuprofen, piroxicam, or indomethacin); a COX2 inhibitor (e.g. celecoxib, rofecoxib, or valdecoxib); an anti-malarial (e.g. hydroxychloroquine); a steroid (e.g. prednisone, prednisolone, budenoside, or dexamethasone); a cytotoxic (e.g. azathioprine, cyclophosphamide, mycophenolate mofetil, or methotrexate); an inhibitor of PDE4, or a purine synthesis inhibitor (e.g. Cellcept®). For example, a compound of formula (I) or a pharmaceutically acceptable salt thereof may be co-administered with sulfasalazine, 5-aminosalicylic acid, olsalazine, Imuran®, an agent that interferes with the synthesis, production, or action of a proinflammatory cytokine (e.g. IL-1), or a caspase inhibitor (e.g. a IL-1 converting enzyme inhibitor or IL-1ra).

A compound of formula (I) or a pharmaceutically acceptable salt thereof may also be co-administered with a T cell signaling inhibitor (e.g. a tyrosine kinase inhibitor), or a molecule that targets T cell activation (e.g. CTLA-4-IgG, an anti-B7 family antibody, or an anti-PD-1 family antibody).

A compound of formula (I) or a pharmaceutically acceptable salt thereof can also be co-administered with an IL-11 antibody, an anti-cytokine antibody (e.g. fonotolizumab (anti-IFNg antibody)), or an anti-receptor receptor antibodies (e.g. an anti-IL-6 receptor antibody or an antibody to a B-cell surface molecule).

A compound of formula (I) or a pharmaceutically acceptable salt thereof can also be co-administered with LJP 394 (abetimus), an agent that depletes or inactivates B-cells (e.g. Rituximab (anti-CD20 antibody) or lymphostat-B (anti-BlyS antibody)), a TNF antagonist (e.g. an anti-TNF antibody), D2E7 (adalimumab), CA2 (infliximab), CDP 571, a TNFR-Ig construct, (p75TNFRigG (etanercept), or p55TNFRigG (LENERCEPT™).

A compound of formula (I) or a pharmaceutically acceptable salt thereof can also be co-administered with one or more agents used in the prevention or treatment of AIDS: an HIV reverse transcriptase inhibitor, an HIV protease inhibitor, an immunomodulator, or another retroviral drug. Examples of reverse transcriptase inhibitors include, but are not limited to, abacavir, adefovir, didanosine, dipivoxil delavirdine, efavirenz, emtricitabine, lamivudine, nevirapine, rilpivirine, stavudine, tenofovir, zalcitabine, and zidovudine. Examples of protease inhibitors include, but are not limited to, amprenavir, atazanavir, darunavir, indinavir, fosamprenavir, lopinavir, nelfinavir, ritonavir, saquinavir, and tipranavir. Examples of other retroviral drugs include, but are not limited to, elvitegravir, enfuvirtide, maraviroc and raltegravir.

For treating type II diabetes, hepatic steatosis, insulin resistance, metabolic syndrome or a related disorder, a compound of formula (I) or a pharmaceutically acceptable salt thereof may be co-administered with insulin or insulins that have been modified to improve the duration of action in the body; agents that stimulate insulin secretion such as acetohexamide, chlorpropamide, glyburide, glimepiride, glipizide, glicazide, glycopyramide, gliquidone, rapaglinide, nataglinide, tolazamide or tolbutamide; agents that are glucagon-like peptide agonists such as exanatide, liraglutide or taspoglutide; agents that inhibit dipeptidyl-peptidase IV such as vildagliptin, sitagliptin, saxagliptin, linagliptin, allogliptin or septagliptin; agents that bind to the peroxisome proliferator-activated receptor gamma such as rosiglitazone or pioglitazone; agents that decrease insulin resistance such as metformin; or agents that reduce glucose absorbance in the small intestine such as acarbose, miglitol or voglibose.

For treating acute kidney disorders or a chronic kidney disease, a compound of formula (I) or a pharmaceutically acceptable salt thereof may be co-administered with dopamine, a diuretic (e.g. furosemide), bumetanide, thiazide, mannitol, calcium gluconate, sodium bicarbonate, albuterol, paricalcitol, doxercalciferol, cinacalcet, or bardoxalone methyl.

The amount of both the compound of formula (I) or salt thereof and additional agent (in those compositions which comprise an additional therapeutic agent as described above) that may be combined with the carrier materials to produce a single dosage form will vary depending upon the host treated and the particular mode of administration. In certain embodiments, compositions of this invention are formulated such that a dosage of between 0.01-100 mg/kg body weight/day of an inventive can be administered.

The additional therapeutic agent and the compound of formula (I) may act synergistically. Therefore, the amount of additional therapeutic agent in such compositions may be less than that required in a monotherapy utilizing only that therapeutic agent, or there may be fewer side effects for the patient given that a lower dose is used. In certain embodiments, in such compositions a dosage of between 0.01-1,000 μg/kg body weight/day of the additional therapeutic agent can be administered.

Provided herein are methods of extending the duration of response to a cytotoxic agent in an individual with cancer comprising administering to the individual (a) an effective amount of a compound of formula (I) or a pharmaceutically acceptable salt thereof and (b) an effective amount of the cytotoxic agent.

In certain embodiments of any of the methods, the cytotoxic agent is a targeted therapy. In certain embodiments, the targeted therapy is one or more of an EGFR antagonist, RAF inhibitor, and/or PI3K inhibitor.

In certain embodiments of any of the methods, the targeted therapy is an EGFR antagonist. In certain embodiments of any of the methods, the EGFR antagonist is N-(3-ethynylphenyl)-6,7-bis(2-methoxyethoxy)-4-quinazolinamine and/or a pharmaceutical acceptable salt thereof. In certain embodiments, the EGFR antagonist is N-(3-ethynylphenyl)-6,7-bis(2-methoxyethoxy)-4-quinazolinamine. In certain embodiments, the EGFR antagonist is N-(4-(3-fluorobenzyloxy)-3-chlorophenyl)-6-(5-((2-(methylsulfonyl)ethylamino)methyl)furan-2-yl)quinazolin-4-amine,di4-methylbenzenesulfonate or a pharmaceutically acceptable salt thereof (e.g., lapatinib).

In certain embodiments of any of the methods, targeted therapy is a RAF inhibitor. In certain embodiments, the RAF inhibitor is a BRAF inhibitor. In certain embodiments, the RAF inhibitor is a CRAF inhibitor. In certain embodiments, the BRAF inhibitor is vemurafenib. In certain embodiments, the RAF inhibitor is 3-(2-cyanopropan-2-yl)-N-(4-methyl-3-(3-methyl-4-oxo-3,4-dihydroquinazolin-6-ylamino)phenyl)benzamide or a pharmaceutically acceptable salt thereof (e.g., AZ628 (CAS#878739-06-1)).

In certain embodiments of any of the methods, the targeted therapy is a PI3K inhibitor.

In certain embodiments of any of the methods, the cytotoxic agent is chemotherapy. In certain embodiments of any of the methods, the chemotherapy is a taxane. In certain embodiments, the taxane is paclitaxel. In certain embodiments, the taxane is docetaxel.

In certain embodiments of any of the methods, the cytotoxic agent is a platinum agent. In certain embodiments, the platinum agent is carboplatin. In certain embodiments, the platinum agent is cisplatin. In certain embodiments of any of the methods, the cytotoxic agent is a taxane and a platinum agent. In certain embodiments, the taxane is paclitaxel. In certain embodiments, the taxane is docetaxel. In certain embodiments, the platinum agent is carboplatin. In certain embodiments, the platinum agent is cisplatin.

In certain embodiments of any of the methods, the cytotoxic agent is a vinca alkyloid. In certain embodiments, the vinca alkyloid is vinorelbine. In certain embodiments of any of the methods, the chemotherapy is a nucleoside analog. In certain embodiments, the nucleoside analog is gemcitabine.

In certain embodiments of any of the methods, the cytotoxic agent is radiotherapy.

In certain embodiments of any of the methods, the compound of formula (I) or a pharmaceutically acceptable salt thereof is concomitantly administered with the cytotoxic agent (e.g., targeted therapy, chemotherapy, and/or radiotherapy). In certain embodiments, the compound of formula (I) or a pharmaceutically acceptable salt thereof is administered prior to and/or concurrently with the cytotoxic agent (e.g., targeted therapy, chemotherapy, and/or radiotherapy).

EXEMPLIFICATION Part I, Synthesis of Intermediate

Step 1: tert-butyl 3-((5-chloro-1-methyl-6-oxo-1,6-dihydropyridazin-4-yl)amino)piperidine-1-carboxylate

4,5-Dichloro-2-methylpyridazin-3(2H)-one (3.57 g, 19.9 mmol), (racemic)-tert-butyl 3-aminopiperidine-1-carboxylate (6.99 g, 34.9 mmol), DBU (3.6 ml, 30 mmol) and DMAc (20 mL) are charged in a sealable vial. The reaction mixture was heated at 120° C. for 15 hours. The reaction mixture was cooled down and partitioned between EtOAc and brine. The organic phase was isolated, and successively washed with brine, water, and brine. The organic phase was evaporated under reduced pressure. The crude residue was purified by flash chromatography on a 80 g-silica gel column (eluent gradient: EtOAc:Hex, 5% to 100%). Two regioisomers were obtained; the later eluting fractions were isolated and evaporated under reduced pressure to afford tert-butyl 3-((5-chloro-1-methyl-6-oxo-1,6-dihydropyridazin-4-yl)amino)piperidine-1-carboxylate (4.33 g, 12.6 mmol) in 63% yield as a racemic mixture. LCMS (ESI+): 343/345 (M+H, Cl pattern).

Step 2: (racemic)-4-chloro-2-methyl-5-(piperidin-3-ylamino)pyridazin-3(2H)-one dihydrochloride

Tert-butyl 3-((5-chloro-1-methyl-6-oxo-1,6-dihydropyridazin-4-yl)amino)piperidine-1-carboxylate (5.2 g, 15 mmol) was dissolved in MeOH (25 mL), and HCl (4M in 1,4-dioxane, 7.6 mL, 30 mmol) is added. The reaction mixture was stirred 4 hours. The reaction mixture was evaporated under reduced pressure. The residue was taken up in DCM (20 mL) and evaporated under reduced pressure. The solid material was triturated with MTBE until a white solid was obtained. The solid material was dried under high vacuum for 16 hours to afford (racemic)-4-chloro-2-methyl-5-(piperidin-3-ylamino)pyridazin-3(2H)-one dihydrochloride (4.4 g, 14 mmol) in 92% yield as a racemic mixture. LCMS (ESI+): 243/245 (M+H, Cl pattern).

Part II, Synthesis of Final Compounds Example 1 4-chloro-2-methyl-5-((1-methylazepan-3-yl)amino)pyridazin-3(2H)-one

4,5-dichloro-2-methylpyridazin-3(2H)-one (200 mg, 1.12 mmol), 1-methylazepan-3-amine (0.29 g, 2.24 mmol), diisopropylamine (0.29 g, 2.24 mmol) and n-BuOH (1 mL) were charged in a microwave vial. The reaction was heated with microwave radiation to 160° C. for 60 min. The volatiles were evaporated under reduced pressure. The crude residue was purified by flash chromatography (silica gel column, 10% to 100% of 1:10:90 NH₄OH:MeOH:DCM in DCM eluent gradient) to afford two sets of fractions containing two regioisomers. The later eluting fractions were evaporated under reduced pressure. The purified solid was re-dissolved in an acetonitrile:water (2:1) mixture, frozen, and lyophilized to afford 4-chloro-2-methyl-5-((1-methylazepan-3-yl)amino)pyridazin-3(2H)-one. ¹H NMR (400 MHz, DMSO-d6) δ 7.87 (s, 1H), 6.20 (d, J=8.8 Hz, 1H), 3.96 (br. s, 1H), 3.60 (s, 3H), 2.55-2.84 (m, 3H), 2.40-2.50 (m, 1H), 12.38 (br. s, 3H), 1.28-1.89 (m, 6H). LCMS (ESI+): 271/273 (M+H, Cl pattern).

The following compounds were prepared in a fashion similar to Example 1.

Examples 2 to 11

m/z Example Compound Name NMR (M + H) 2 4-chloro-2-methyl-5-((1- 257 methylpiperidin-4- yl)amino)pyridazin-3(2H)- one 3 (racemic)-4-chloro-2- ¹H NMR (400 MHz, DMSO-d6) δ 7.89 (s, 257 methyl-5-((1- 1H), 5.88-5.90 (m, 1H), 3.85-3.89 (m, 1H), methylpiperidin-3- 3.57 (s, 3H), 2.53-2.56 (m, 1H), yl)amino)pyridazin-3(2H)- 2.29-2.38 (m, 2H), 2.22-2.25 (m, 1H), 2.17 (s, 3H), one 1.46-1.62 (m, 4H). 4 (racemic)-4-chloro-2- ¹H NMR (400 MHz, DMSO-d6) δ 7.85 (s, 271 methyl-5-((1-methylazepan- 1H), 6.26 (d, J = 9.4 Hz, 1H), 4-yl)amino)pyridazin- 3.98-4.03 (m, 1H), 3.58 (s, 3H), 2.51-2.61 (m, 1H), 3(2H)-one 2.43-2.48 (m, 2H), 2.27 (s, 3H), 1.80-1.86 (m, 2H), 1.73-1.76 (m, 2H), 1.54-1.70 (m, 3H). 5 4-chloro-2-methyl-5- ¹H NMR (400 MHz, DMSO-d6) δ 7.89 (s, 283 (((1R,3r,5S)-8-methyl-8- 1H), 6.00 (d, J = 8.9 Hz, 1H), azabicyclo[3.2.1]octan-3- 3.80-3.86 (m, 1H), 3.56 (s, 3H), 3.06 (br. s, 2H), yl)amino)pyridazin-3(2H)- 2.20 (s, 3H), 1.87-1.91 (m, 2H), 1.67-1.76 (m, one 4H), 1.57-1.62 (m, 2H). 6 4-chloro-2-methyl-5- ¹H NMR (400 MHz, DMSO-d6) δ 7.72 (s, 283 (((1R,3s,5S)-8-methyl-8- 1H), 5.61 (d, J = 6.7 Hz, 1H), azabicyclo[3.2.1]octan-3- 3.89-3.91 (m, 1H), 3.58 (s, 3H), 3.04 (br. s, 2H), yl)amino)pyridazin-3(2H)- 2.14 (s, 3H), 2.05-2.12 (m, 2H), 1.96-2.00 (m, one 2H), 1.70-1.76 (m, 2H), 1.65 (d, J = 14.6 Hz, 2H). 7 (R)-5-((1-benzylpiperidin-3- ¹H NMR (400 MHz, DMSO-d6) d 7.84 (s, 333 yl)amino)-4-chloro-2- 1H), 7.32 (d, J = 3.94 Hz, 4H), 7.25 (d, J = 3.94 Hz, methylpyridazin-3(2H)-one 1H), 5.94 (d, J = 8.54 Hz, 1H), 3.87 (br. s., 1H), 3.57 (s, 3H), 3.42-3.54 (m, 2H), 2.56 (d, J = 9.42 Hz, 1H), 2.26-2.47 (m, 3H), 1.46-1.74 (m, 4H). 8 (S)-5-((1-benzylpiperidin-3- ¹H NMR (400 MHz, DMSO-d6) δ 333 yl)amino)-4-chloro-2- 9.83-10.19 (m, 1H), 7.80 (s, 1H), 7.40-7.57 (m, methylpyridazin-3(2H)-one 6H), 6.48 (d, J = 8.87 Hz, 1H), 4.24-4.44 (m, 2H), 3.57-3.61 (m, 3H), 3.27-3.53 (m, 3H), 2.62-2.90 (m, 2H), 1.92 (d, J = 11.25 Hz, 2H), 1.49-1.79 (m, 2H). 9 4-chloro-2-methyl-5-((1- ¹H NMR (400 MHz, DMSO-d6) δ 8.10 (d, 320 (pyridin-2-yl)piperidin-3- J = 3.72 Hz, 1H), 8.01 (s, 1H), yl)amino)pyridazin-3(2H)- 7.45-7.59 (m, 1H), 6.88 (d, J = 8.54 Hz, 1H), one 6.62 (dd, J = 5.26, 6.35 Hz, 1H), 6.19 (d, J = 8.32 Hz, 1H), 4.29 (d, J = 11.61 Hz, 1H), 4.02 (d, J = 13.14 Hz, 1H), 3.67-3.81 (m, 1H), 3.56-3.64 (m, 3H), 2.89-3.06 (m, 2H), 1.95 (d, J = 8.98 Hz, 1H), 1.64-1.83 (m, 2H), 1.54 (d, J = 11.17 Hz, 1H). 10 (racemic)-4-chloro-2- ¹H NMR (400 MHz, DMSO-d6) δ 7.46 (s, 269 methyl-5-(quinuclidin-3- 1H), 4.82 (d, J = 6.6 Hz, 1H), 3.77 (s, 3H), ylamino)pyridazin-3(2H)- 3.72-3.74 (m, 1H), 3.47-3.53 (m, 1H), one 2.89-2.99 (m, 4H), 2.70-2.75 (m, 1H), 2.03 (dd, J = 3.1, 6.1 Hz, 1H), 1.80-1.87 (m, 2H), 1.70-1.72 (m, 1H), 1.55-1.65 (m, 1H). 11 (racemic)-4-chloro-2- ¹H NMR (400 MHz, DMSO-d6) δ 7.94 (s, 244 methyl-5-((tetrahydro-2H- 1H), 5.97-5.99 (m, 1H), 3.70-3.81 (m, 4H), pyran-3-yl)amino)pyridazin- 3.58 (s, 3H), 1.91 (br. s, 1H), 1.60-1.67 (m, 3(2H)-one 3H), 1.44-1.51 (m, 1H).

Example 12 2,4-dimethyl-5-((1-methylazepan-3-yl)amino)pyridazin-3(2H)-one

4-chloro-2-methyl-5-((1-methylazepan-3-yl)amino)pyridazin-3(2H)-one (15 mg, 0.055 mmol), methylboronic acid (0.008 g, 0.14 mmol), potassium phosphate (25 mg, 0.11 mmol), and SPhos 3^(rd) generation precatalyst (2 mg, 0.003 mmol) were all put in a sealable vial. The vial was flushed with nitrogen, then 1,4-dioxane (0.8 mL) and water (0.2 mL) were added. Mixture was degassed with nitrogen and heated to 100° C. for 3 hours. The organic supernatant was isolated and evaporated under reduced pressure. The crude residue was purified using chromatography (12 g-silica gel column, 10% to 100% of 1:10:90 NH₄OH:MeOH:DCM in DCM eluent gradient). The pure fractions were isolated and evaporated under reduced pressure. The solid was redissolved in acetonitrile:water (2:1), frozen, and lyophilized to afford 2,4-dimethyl-5-((1-ethylazepan-3-yl)amino)pyridazin-3(2H)-one (7 mg, 0.027 mmol) in 49% yield. ¹H NMR (400 MHz, DMSO-d6) δ 7.67 (s, 1H), 5.43 (d, J=9.0 Hz, 1H), 3.88-3.70 (m, 1H), 3.52 (s, 3H), 2.74-2.62 (m, 1H), 2.60-2.51 (m, 3H), 2.40-2.29 (m, 3H), 1.83 (s, 3H), 1.76-1.36 (m, 6H). LCMS (ESI+): 251 (M+H).

Example 13 4-bromo-2-methyl-5-((1-methylazepan-3-yl)amino)pyridazin-3(2H)-one

Step 1: 4-bromo-5-chloro-2-methylpyridazin-3(2H)-one

4,5-dichloro-2-methylpyridazin-3(2H)-one (180 mg, 1.01 mmol) was dissolved in 48% aqueous HBr (5 mL, 45 mmol). The reaction mixture was heated at 100° C. for 16 hours. The reaction mixture was cooled down and basified up to pH=8 with 1M aq. NaOH. The mixture was extracted with EtOAc. The organic layer was washed with brine, dried with Na₂SO₄, filtered and evaporated under reduced pressure to afford a mixture of 4-bromo-5-chloro-2-methylpyridazin-3(2H)-one and 5-bromo-4-chloro-2-methylpyridazin-3(2H)-one (280 mg, 1.253 mmol) in quantitative yield. LCMS (ESI+): 223/225/227 (M+H, Br, Cl pattern).

Step 2: 4-bromo-2-methyl-5-((1-methylazepan-3-yl)amino)pyridazin-3(2H)-one

The 4-bromo-5-chloro-2-methylpyridazin-3(2H)-one and 5-bromo-4-chloro-2-methylpyridazin-3(2H)-one (280 mg, 1.253 mmol), 1-methylazepan-3-amine (0.209 g, 1.63 mmol), N-ethyl-N-isopropylpropan-2-amine (0.243 g, 1.88 mmol) and n-BuOH (1.5 mL) were charged in a microwave vial. The reaction was heated to 160° C. for 60 min. The mixture of regioisomers was purified by flash chromatography (10% to 100% of 1:10:90 NH₄OH:MeOH:DCM in DCM eluent gradient) to afford two sets of fractions. The later eluting fractions (most polar compound) were combined and evaporated under reduced pressure to afford 4-bromo-2-methyl-5-((1-methylazepan-3-yl)amino)pyridazin-3(2H)-one (155 mg, 0.395 mmol) in 39% yield. ¹H NMR (400 MHz, DMSO-d6) δ 7.77 (s, 1H), 6.20 (d, J=8.8 Hz, 1H), 3.96 (br. s, 1H), 3.57 (s, 3H), 2.55-2.75 (m, 3H), 2.34-2.45 (m, 1H), 2.37 (s, 3H), 1.31-1.74 (m, 6H). LCMS (ESI+): 315/317 (M+H, Br pattern).

Example 14 4-chloro-2-isopropyl-5-((1-methylazepan-3-yl)amino)pyridazin-3(2H)-one

Step 1 4,5-dichloro-2-isopropylpyridazin-3(2H)-one

A disposable reaction tube was charged with 4,5-dichloropyridazin-3(2H)-one (0.165 g, 1.00 mmol), cesium carbonate (0.652 g, 2.00 mmol), and a stirbar. Acetonitrile (5 mL) was added, followed by 2-bromopropane (0.188 mL, 2.00 mmol), and the reaction was stirred at 50° C. 18 hours. The mixture was filtered, concentrated in vacuo with celite, and purified by silica gel chromatography (eluting with hexanes/ethyl acetate) to afford the title compound as a white amorphous solid (30 mg, 0.14 mmol, 14% yield). LCMS (ESI+): (M+H) 208.

Step 2: 4-chloro-2-isopropyl-5-((1-methylazepan-3-yl)amino)pyridazin-3(2H)-one

A microwave vial was charged with 4,5-dichloro-2-isopropylpyridazin-3(2H)-one (30 mg, 0.14 mmol) and a stirbar. n-BuOH (2 mL) was added, followed by 1-methylazepan-3-amine (36 mg, 0.28 mmol) and N-ethyl-N-isopropylpropan-2-amine (0.35 mL, 0.28 mmol). The solution was stirred at 160° C. for 4 hours before being diluted with methanol/water and filtered. Purification by reversed phase HPLC (eluting with water/acetonitrile/0.1% trifluoroacetic acid), followed by lyophilization gave the title compound as an off-white amorphous solid (6.9 mg, 0.023 mmol, 16% yield). LCMS (ESI+): 299 (M+H)

The following compounds were prepared in a similar fashion to Example 14.

Examples 15, 16 and 17

Example 15 was obtained using iodoethane instead of 2-bromopropane; Example 16 was obtained using (bromomethyl)cyclopropane instead of 2-bromopropane; Example 17 was obtained using trans-crotyl chloride instead of 2-bromopropane.

m/z Example Compound Name NMR (M + H) 15 4-chloro-2-ethyl-5-((1- ¹H NMR (400 MHz, DMSO-d6) δ 7.90 (s, 285 methylazepan-3- 1H), 6.21 (d, J = 8.98 Hz, 1H), 4.02 (dq, J = 0.99, yl)amino)pyridazin- 7.12 Hz, 2H), 3.90-3.98 (m, 1H), 3(2H)-one 2.56-2.77 (m, 3H), 2.41-2.48 (m, 1H), 2.36 (s, 3H), 1.43-1.76 (m, 6H), 1.21 (t, J = 7.12 Hz, 3H). 16 4-chloro-2- ¹H NMR (500 MHz, DMSO-d6) δ 7.91 (s, 311 (cyclopropylmethyl)- 1H), 6.24 (d, J = 8.55 Hz, 1H), 3.92-4.02 (m, 5((1-methylazepan-3- 1H), 3.86 (dd, J = 1.83, 7.20 Hz, 2H), yl)amino)pyridazin- 2.58-2.83 (m, 3H), 2.43-2.49 (m, 1H), 2.39 (s, 3H), 3(2H)-one 1.46-1.76 (m, 6H), 1.13-1.24 (m, 1H), 0.38-0.49 (m, 2H), 0.27-0.37 (m, 2H). 17 (E)-2-(but-2-en-1-yl)- 311 4-chloro-5-((1- methylazepan-3- yl)amino)pyridazin- 3(2H)-one

Example 18 Racemic 4-chloro-5-(((3R*,5S*)-5-isobutyl-1-methylpiperidin-3-yl)amino)-2-methylpyridazin-3(2H)-one

Step 1: tert-butyl 2-(tert-butoxycarbonyl)-2-(5-bromopyridin-3-yl)carbamate

To a stirred and cooled (0° C.) solution of 5-bromopyridin-3-amine (50.0 g, 289 mmol) in THF (1.0 L) was added LiHMDS (1 M in THF, 636 mL, 636 mmol). After addition, stirring was continued for 1 h at room temperature before di-tert-butyl dicarbonate (138.8 g, 635.8 mmol) was added. The reaction mixture was then stirred at room temperature for 15 h, at which time LCMS indicated that the reaction had gone to completion. The reaction was quenched by addition of saturated aqueous ammonium chloride (300 mL). The reaction mixture was partitioned between ethyl acetate (1000 mL) and water (400 mL). The organic layer was washed with brine (2×100 mL), dried over Na₂SO₄ and concentrated under reduced pressure. The crude product was purified by silica gel chromatography (petroleum ether:ethyl acetate=5:1) to afford the title compound (45.6 g, 42% yield) as a white solid. LCMS (ESI+): 373/375 (M+H, Br pattern).

Step 2: tert-butyl (5-isobutylpyridin-3-yl)carbamate

To a stirred and cooled (0° C.) suspension of tert-butyl 2-(tert-butoxycarbonyl)-2-(5-bromopyridin-3-yl)carbamate (40.0 g, 107 mmol) and zinc(II) chloride (87.43 g, 641.0 mmol) in THF (400 mL) was added isobutylmagnesium chloride (1.0 M in THF, 643 mL, 643.0 mmol) under nitrogen atmosphere. After addition, stirring was continued for 20 min at room temperature before Pd(dppf)Cl₂ (4.0 g, 5.5 mmol) was added. The reaction mixture was then stirred heated at 50° C. for 2 h, at which time LCMS indicated that the reaction had gone to completion. The reaction mixture was quenched by addition of saturated aqueous ammonium chloride (100 mL) and then partitioned between ethyl acetate (500 mL) and water (200 mL). The separated organic layer was washed with brine (2×100 mL), dried over Na₂SO₄ and concentrated under reduced pressure. The crude product was purified by silica gel chromatography (petroleum ether:ethyl acetate=5:1) to give the title compound (20.0 g, 80% yield) as a white solid.

Step 3: tert-butyl 2-(tert-butoxycarbonyl)-2-(5-isobutylpyridin-3-yl)carbamate

To a stirred and cooled (0° C.) solution of tert-butyl (5-isobutylpyridin-3-yl)carbamate (20.0 g, 78.89 mmol) in THF (400 mL) was added LiHMDS (1.0 M, 95.9 mL, 95.90 mmol). After addition, stirring was continued for 1 h at room temperature before di-tert-butyl dicarbonate (20.9 g, 95.76 mmol) was added. The reaction mixture was then stirred at room temperature for 15 h, at which time LCMS indicated that the reaction had gone to completion. The mixture was quenched by addition of saturated aqueous ammonium chloride (100 mL) and then partitioned between ethyl acetate (600 mL) and water (200 mL). The separated organic layer was washed with brine (2×100 mL), dried over Na₂SO₄ and concentrated under reduced pressure. The crude product was purified by silica gel chromatography (petroleum ether:ethyl acetate=5:1) to give the title compound (25.5 g, 91% yield) as a white solid.

Step 4: 3-((di-tert-butoxycarbonyl)amino)-5-isobutyl-1-methylpyridin-1-ium iodide

To a stirred and cooled (0° C.) solution of tert-butyl 2-(tert-butoxycarbonyl)-2-(5-isobutylpyridin-3-yl)carbamate (25.5 g, 72.8 mmol) in toluene (400 mL) was added iodomethane (31.0 g, 218 mmol). After addition, the reaction mixture was heated to 110° C. for 3 h, at which time LCMS indicated that the reaction had gone to completion. The solvent was removed under reduced pressure to give the crude title compound (33.0 g, 92% yield) as a red solid. This crude was used in the next step without further purification.

Step 5: Racemic-tert-Butyl 2-(tert-butoxycarbonyl)-2-((3RS,5SR)-5-isobutyl-1-methylpiperidin-3-yl)carbamate

A mixture of 3-((di-tert-butoxycarbonyl)amino)-5-isobutyl-1-methylpyridin-1-ium iodide (33.0 g, 63.02 mmol), PtO₂ (3.3 g) and acetic acid (12.1 g, 201 mmol) in methanol (50 mL) was hydrogenated (4 atm) at 60° C. for 48 h, at which time TLC indicated that the reaction had gone to completion. The solid was removed by filtration (warning! flammable solid) and the filtrate was concentrated under reduced pressure to give the crude title compound (14.0 g, 56% yield) as a yellow solid. This crude material was used in the next step without further purification.

Step 6: Racemic-(3RS,5SR)-5-isobutyl-1-methylpiperidin-3-amine dihydrochloride

To a solution of Racemic-tert-Butyl 2-(tert-butoxycarbonyl)-2-((3RS,5SR)-5-isobutyl-1-methylpiperidin-3-yl)carbamate (14.0 g, 37.8 mmol) in methanol (100 mL) was added HCl (2 N in methanol, 60 mL). The reaction mixture was stirred at room temperature for 30 min and then concentrated under reduced pressure to give the crude title compound (8.0 g, 82% yield) as a pale yellow solid. This material was used directly in the next step without further purification.

Step 7: Racemic 4-chloro-5-(((3RS,5SR)-5-isobutyl-1-methylpiperidin-3-yl)amino)-2-methylpyridazin-3(2H)-one

The following reaction was performed in twenty parallel batches. A mixture of 4,5-dichloro-2-methylpyridazin-3(2H)-one (500 mg, 2.79 mmol), racemic (3RS,5SR)-5-isobutyl-1-methylpiperidin-3-amine dihydrochloride (815 mg, 3.35 mmol) and N-ethyl-N-isopropylpropan-2-amine (1.81 g, 14.0 mmol) in isopropanol (5 mL) was heated at 150° C. under microwave conditions for 2 h, at which time LCMS indicated the reaction had gone to completion. The reaction mixtures were pooled and concentrated under reduced pressure. The crude residue was purified by reverse phase HPLC (acetonitrile 30-60%/0.1% NH₄OH in water) to afford (racemic)-4-chloro-5-(((3R,5S)-5-isobutyl-1-methylpiperidin-3-yl)amino)-2-methylpyridazin-3(2H)-one.

Examples 19 and 20 4-chloro-5-(((3S,5R)-5-isobutyl-1-methylpiperidin-3-yl)amino)-2-methypyridazin-3(2H)-one and 4-chloro-5-(((3R,5S)-5-isobutyl-1-methylpiperidin-3-yl)amino)-2-methylpyridazin-3(2H)-one

(racemic)-4-chloro-5-(((3R,5S)-5-isobutyl-1-methylpiperidin-3-yl)amino)-2-methylpyridazin-3(2H)-one was separated using chiral SFC (SFC80; Chiralpak OD 300×50 mm I.D.,10 Lm; Supercritical CO₂/EtOH+NH₄OH=20/80; 200 mL/min) to give the title compounds: Example 19 (450 mg, 3% over 2 steps) as a white solid. ¹H NMR (400 MHz, DMSO-d₆) δ 7.91 (s, 1H), 6.02 (d, J=8.8 Hz, 1H), 3.83-3.75 (m, 1H), 3.57 (s, 3H), 2.84-2.81 (m, 1H), 2.72-2.69 (m, 1H), 2.17 (s, 3H), 1.82-1.61 (m, 4H), 1.44-1.38 (m, 1H), 1.08-0.98 (m, 3H), 0.85 (d, J=6.0 Hz, 6H). LCMS (ESI+): 313/315 (M+H, Cl pattern).

Example 20 (475 mg, 3% over 2 steps) as a white solid. ¹H NMR (400 MHz, DMSO-d₆) δ 7.91 (s, 1H), 6.02 (d, J=8.8 Hz, 1H), 3.83-3.75 (m, 1H), 3.57 (s, 3H), 2.85-2.81 (m, 1H), 2.72-2.69 (m, 1H), 2.17 (s, 3H), 1.82-1.61 (m, 4H), 1.45-1.41 (m, 1H), 1.08-0.98 (m, 3H), 0.85 (d, J=6.0 Hz, 6H). LCMS (ESI+): 313/315 (M+H, CI pattern).

Examples 21-23 were prepared in a similar fashion to Examples 18-20.

Examples 21-23

Example Compound Name NMR m/z 21 (racemic)-4-chloro-5- 271 (((3RS,5SR)-1,5- dimethylpiperidin-3- yl)amino)-2- methylpyridazin-3(2H)-one 22 4-chloro-5-(((3R,5S)-1,5- ¹H NMR (400 MHz, Methanol-d4) δ 7.84 (s, 271 dimethylpiperidin-3- 1H), 3.75-3.70 (m, 4H), 3.00-2.97 (m, 1H), yl)amino)-2- 2.83-2.81 (m, 1H), 2.32 (s, 3H), methylpyridazin-3(2H)-one 2.01-1.98 (m, 1H), 1.89-1.84 (m, 2H), 1.64-1.58 (m, 1H), 1.11-1.05 (m, 1H), 0.95 (d, J = 6.4 Hz, 3H). (Note: exchangeable NH proton) 23 4-chloro-5-(((3S,5R)-1,5- ¹H NMR (400 MHz, Methanol-d4) δ 7.84 (s, 271 dimethylpiperidin-3- 1H), 3.78-3.70 (m, 4H), 3.00-2.97 (m, 1H), yl)amino)-2- 2.84-2.81 (m, 1H), 2.32 (s, 3H), methylpyridazin-3(2H)-one 2.01-1.98 (m, 1H), 1.90-1.84 (m, 2H), 1.65-1.58 (m, 1H), 1.11-1.05 (m, 1H), 0.95 (d, J = 6.4 Hz, 3H). (Note exchangeable NH proton)

Example 24 4-chloro-2-methyl-5-((1-methyl-5-phenylpiperidin-3-yl)amino)pyridazin-3(2H)-one

Step 1: tert-butyl 2-(tert-butoxycarbonyl)-2-(5-phenylpyridin-3-yl)carbamate

tert-butyl 2-(tert-butoxycarbonyl)-2-(5-bromopyridin-3-yl)carbamate (7.5 g, 20 mmol), sodium carbonate (4.26 g, 40.5 mmol) and phenylboronic acid (2.82 g, 23.1 mmol) were dissolved in 1,4-dioxane (80 mL) and water (30 mL). The reaction mixture was degassed using vacuum/nitrogen cycles. The reaction mixture was heated to 80° C. for 1.5 hour. The reaction mixture was partitioned between EtOAc and saturated aqueous NaHCO₃. The organic phase was evaporated under reduced pressure and dried under high vacuum to afford the tert-butyl 2-(tert-butoxycarbonyl)-2-(5-phenylpyridin-3-yl)carbamate (7.44 g 20.09 mmol) in quantitative yield. LCMS (ESI+): 371 (M+H)

Step 2: 3-((di-tert-butoxycarbonyl)amino)-5-phenyl-1-methylpyridin-1-ium iodide

tert-butyl 2-(tert-butoxycarbonyl)-2-(5-phenylpyridin-3-yl)carbamate (4.00 g, 10.8 mmol) was dissolved in toluene (10 mL). Iodomethane (1 mL, 15 mmol) was added and the reaction mixture was heated to 60° C. for 16 hours. The volatiles were evaporated under reduced pressure to afford 3-((di-tert-butoxycarbonyl)amino)-5-isobutyl-1-methylpyridin-1-ium iodide (5.53 g, 10.8 mmol) in quantitative yield. LCMS (ESI+): 385 (M+H)

Step 3: Racemic-(1-methyl-5-phenylpiperidin-3-yl)carbamate

To a solution of 3-((di-tert-butoxycarbonyl)amino)-5-isobutyl-1-methylpyridin-1-ium iodide (5.53 g, 10.8 mmol) in THF (60 mL) was added water (5 mL). The reaction mixture was cooled to 0° C. and sodium borohydride (2.69 g, 71.1 mmol) was cautiously added (portionwise). The reaction mixture was stirred for 4 hours, quenched with a saturated aqueous solution of ammonium chloride and extracted with EtOAc (3×100 mL). The combined organic phases were dried with Na₂SO₄, filtered, and evaporated under reduced pressure. The crude residue dissolved in EtOAc (5 mL) and transferred to a sealable tube equipped with pressure gauge. Palladium hydroxide (10% on charcoal) was added, followed by MeOH (20 mL). The reaction was stirred for 48 hours under hydrogen (50 psi). The reaction was filtered on celite (caution! Pyrophoric solid) and the cake was washed with EtOAc. The filtrate was evaporated under reduced pressure to afford a mixture of species containing racemic tert-butyl (1-methyl-5-phenylpiperidin-3-yl)carbamate (2.56 g, 8.82 mmol) in 82% yield. LCMS (ESI+): 291 (M+H).

Step 4: racemic 1-methyl-5-phenylpiperidin-3-amine dihydrochloride

tert-butyl (1-methyl-5-phenylpiperidin-3-yl)carbamate (250 mg, 0.86 mmol) dissolved in methanol (2 mL) was treated with HCl (4M in 1,4-dioxane) (0.86 mL, 3.4 mmol). After stirring for 3 hours, the reaction was evaporated under reduced pressure. The residue was dried under high vacuum to afford 1-methyl-5-phenylpiperidin-3-amine dihydrochloride (0.23 g, 0.87 mmol) in quantitative yield. LCMS (ESI+): 191 (M+H).

Step 5: (racemic)-4-chloro-2-methyl-5-((1-methyl-5-phenylpiperidin-3-yl)amino)pyridazin-3(2H)-one

4,5-dichloro-2-methylpyridazin-3(2H)-one (200 mg, 1.12 mmol), 1-methyl-5-phenylpiperidin-3-amine dihydrochloride (230 mg, 0.88 mmol), diisopropylethylamine (880 μL, 0.64 g, 4.92 mmol) and DMAc (3 mL) were charged in a sealable vial. The reaction was heated to 120° C. for 4 hours. The reaction mixture is partitioned between EtOAc and a saturated aqueous solution of NaHCO₃. The organic phase was washed with brine, dried with Na₂SO₄ and filtered. The volatiles were removed under reduced pressure. The crude residue was purified by silica gel chromatography (0% to 100% of 1:10:90 NH₄OH:MeOH:DCM in DCM as eluent gradient) to afford two sets of fractions. The later eluting fractions (more polar compounds) were combined and evaporated under reduced pressure. The compound was re-purified preparative reversed phase HPLC (water:acetonitrile with 0.1% of trifluoroacetic acid, SunFire column). The pure fractions were frozen and lyophilized to afford (racemic)-4-chloro-2-methyl-5-((1-methyl-5-phenylpiperidin-3-yl)amino)pyridazin-3(2H)-one trifluoroacetatic acid salt (43 mg, 0.10 mmol) in 8% yield. LCMS (ESI+): 333/335 (M+H, Cl pattern).

Example 25 4-chloro-5-((1,6-dimethylpiperidin-3-yl)amino)-2-methylpyridazin-3(2H)-one

Step 1: tert-butyl 2-(tert-butoxycarbonyl)-2-(6-methylpyridin-3-yl)carbamate

6-methylpyridin-3-amine (2.0 g, 18.5 mmol) was dissolved in THF (75 mL). The reaction was cooled to 0° C., then sodium hexamethyldisilazane (LM solution in THF) (42.5 ml, 42.5 mmol) was added dropwise. The reaction mixture was warmed to 25° C. and stirred 30 minutes. Di-tert-butyl dicarbonate (8.47 g, 38.83 mmol) dissolved in 10 mL THF was then added in one portion. The reaction mixture was stirred overnight at room temperature then poured in water/brine mixture (1/1). The solution was extracted with EtOAc (2×250 mL). The combined organic phases were dried with Na₂SO₄, filtered, and evaporated under reduced pressure. The residue was frozen in dry ice, put under high vacuum, and thawed to afford tert-butyl 2-(tert-butoxycarbonyl)-2-(6-methylpyridin-3-yl)carbamate (5.4 g, 18.49 mmol) in 95% yield as a tan solid. LCMS (ESI+): 309 (M+H).

Step 2: 3-((di-tert-butoxycarbonyl)amino)-6-methyl-1-methylpyridin-1-ium iodide

tert-butyl 2-(tert-butoxycarbonyl)-2-(6-methylpyridin-3-yl)carbamate (4 g, 8.88 mmol) was dissolved in toluene (20 mL). Iodomethane (1 mL, 16.9 mmol) was added and the reaction mixture was heated at 60° C. for 24 hours. The reaction mixture was evaporated under reduced pressure to afford 3-((di-tert-butoxycarbonyl)amino)-6-methyl-1-methylpyridin-1-ium iodide (4.1 g, 8.88 mmol) in quantitative yield. LCMS (ESI+): 324.1 (M+, no iodide)

Step 3: tert-butyl (1,6-dimethylpiperidin-3-yl)carbamate

To a solution of 3-((di-tert-butoxycarbonyl)amino)-6-methyl-1-methylpyridin-1-ium iodide (4.1 g, 8.88 mmol) in THF (45 mL), was added water (5 mL). The reaction mixture was cooled to 0° C. Sodium borohydride (1.38 g, 36.4 mmol) was cautiously added (portionwise). After 4 hours, the reaction mixture quenched with a saturated aqueous solution of ammonium chloride. The reaction mixture was extracted with EtOAc (2×100 mL). The combined organic phases were dried with Na₂SO₄, filtered and evaporated under reduced pressure. The crude residue re-dissolved in EtOAc (5 mL), transferred to a sealable tube equipped with a pressurization adapter. Palladium (10% on charcoal) (3 g) was added, followed by MeOH (20 mL). The reaction stirred for 48 hours under an atmosphere of hydrogen (50 psi). The reaction mixture was filtered on celite and the solid cake was washed with EtOAc. The filtrate was evaporated under reduced pressure. The crude residue was purified (120 g-silica column, 0 to 100% of 1:10:90 NH₄OH:MeOH:DCM in DCM) to afford tert-butyl (1,6-dimethylpiperidin-3-yl)carbamate (2.99 g, 9.1 mmol) in quantitative yield. LCMS (ESI+): 329 (M+H).

Step 4: 1,6-dimethylpiperidin-3-amine dihydrochloride

tert-butyl (1,6-dimethylpiperidin-3-yl)carbamate (390 mg, 1.19 mmol) was dissolved in MeOH (1 mL). HCl (4M in dioxane) (1.19 mL, 5.6 mmol) was added. The reaction mixture was stirred for 60 hours. The reaction mixture was evaporated to afford 1,6-dimethylpiperidin-3-amine dihydrochloride (0.26 g, 1.27 mmol). LCMS (ESI+): 129 (M+H).

Step 5: 4-chloro-5-((1,6-dimethylpiperidin-3-yl)amino)-2-methylpyridazin-3(2H)-one

4,5-dichloro-2-methylpyridazin-3(2H)-one (240 mg, 1.34 mmol), 1,6-dimethylpiperidin-3-amine dihydrochloride (0.27 g, 1.341 mmol), N,N-diisopropylethylamine (771 μL, 4.43 mmol) and DMAc (1.3 mL) were charged in a sealable vial. The reaction was heated to 120° C. for 2 hours. The reaction mixture was purified by preparative reversed phase HPLC (water:acetonitrile with 0.1% trifluoroacetic acid, SunFire column). The earlier eluting fractions were collected and lyophilized to afford 4-chloro-5-((1,6-dimethylpiperidin-3-yl)amino)-2-methylpyridazin-3(2H)-one trifluoroacetic acid (61 mg, 0.17 mmol) in 13% yield as a 2:1 mixture of diastereomers.

LCMS (ESI+): 271/273 (M+H, Cl pattern).

Examples 26-29

The four stereoisomers of Example 25 (4-chloro-5-((1,6-dimethylpiperidin-3-yl)amino)-2-methylpyridazin-3(2H)-one) were isolated using a PIC-100 supercritical phase chromatography (Chiralpak AD; 2×10 cm; Isocratic 15% Methanol w/0.1% NH₄OH; 100 bar; 40° C.; 70 mL/min; 220 nm) to afford Examples 26-29.

Example 30 4-chloro-5-((1-(2-methoxyethyl)piperidin-3-yl)amino)-2-methylpyridazin-3(2H)-one

To a solution of 4-chloro-2-methyl-5-(piperidin-3-ylamino)pyridazin-3(2H)-one dihydrochloride (100 mg, 0.32 mmol) in acetonitrile (1.5 mL), was added N,N-diisopropylamine (220 μL, 1.26 mmol), and 1-bromo-2-methoxyethane (50 mg, 0.72 mmol). After stirring for 2 hours at 25° C., the volatiles were evaporated and the crude residue was purified by chromatography (10 g-silica gel column, 0% to 100% of 1:10:90 NH₄OH:MeOH:DCM in DCM as eluent gradient) to afford 4-chloro-5-((1-(2-methoxyethyl)piperidin-3-yl)amino)-2-methylpyridazin-3(2H)-one (41 mg, 0.137 mmol) in 42% yield. LCMS (ESI+): 301 (M+H).

Example 31 4-chloro-2-methyl-5-((1-(oxetan-3-yl)piperidin-3-yl)amino)pyridazin-3(2H)-one

4-chloro-2-methyl-5-(piperidin-3-ylamino)pyridazin-3(2H)-one dihydrochloride (105 mg, 0.34 mmol), oxetan-3-one (0.06 g, 0.78 mmol) and sodium triacetoxyborohydride (0.17 g, 0.78 mmol) were dissolved in THF. After heating to 40° C. for 2 hours, the volatiles were evaporated under reduced pressure. The crude residue was purified by silica gel chromatography (24 g-silica gel column, 0% to 100% 1:10:90 NH₄OH:MeOH:DCM in DCM as eluent gradient). Pure fractions were evaporated under reduced pressure to afford 4-chloro-2-methyl-5-((1-(oxetan-3-yl)piperidin-3-yl)amino)pyridazin-3(2H)-one (25 mg, 0.08 mmol) in 21% yield. LCMS (ESI+): 299/301 (M+H, Cl pattern).

Example 32 4-chloro-5-((1-isopropylpiperidin-3-yl)amino)-2-methylpyridazin-3(2H)-one

To a solution of 4-chloro-2-methyl-5-(piperidin-3-ylamino)pyridazin-3(2H)-one dihydrochloride (75 mg, 0.27 mmol) in THF (2 mL) was added 2-methoxyprop-1-ene (0.03 g, 0.44 mmol), followed by NaBH(OAc)₃ (155 mg, 0.73 mmol). The reaction mixture was stirred at 25° C. for 16 hours. Acetone (0.5 mL) was added and the reaction mixture was stirred for 16 hours. The volatiles were removed under reduced pressure. The crude residue was purified by silica gel chromatography (0% to 100% 1:10:90 NH₄OH:MeOH:DCM in DCM as eluent gradient). Pure fractions were evaporated under reduced pressure. The compound was re-dissolved in acetonitrile:water mixture, frozen and lyophilized to afford 4-chloro-5-((1-isopropylpiperidin-3-yl)amino)-2-methylpyridazin-3(2H)-one (37 mg, 0.13 mmol) in 48% yield. ¹H NMR (400 MHz, DMSO-d6) δ 7.87 (s, 1H), 5.94 (d, J=9.0 Hz, 1H), 3.83-3.87 (m, 1H), 3.57 (s, 3H), 2.73-2.76 (m, 1H), 2.56-2.62 (m, 1H), 2.39-2.45 (m, 3H), 1.47-1.63 (m, 4H), 0.97 (d, J=6.1 Hz, 3H), 0.94 (d, J=6.1 Hz, 3H). LCMS (ESI+): 285/287

Example 33 4-chloro-2-methyl-5-((1-(pyridin-2-ylmethyl)piperidin-3-yl)amino)pyridazin-3(2H)-one

4-chloro-2-methyl-5-(piperidin-3-ylamino)pyridazin-3(2H)-one dihydrochloride (60 mg, 0.19 mmol) suspended in acetonitrile. DIEA (98 mg, 0.76 mmol) was added followed by 2-(bromomethyl)pyridine hydrobromide (65 mg, 0.258 mmol). Heated to 50° C. for 4 hours. The volatiles were removed under reduced pressure. The crude residue was purified by silica gel chromatography (0% to 100% 1:10:90 NH₄OH:MeOH:DCM in DCM as eluent gradient). Pure fractions were evaporated under reduced pressure. The compound was re-dissolved in acetonitrile:water mixture, frozen and lyophilized to afford 4-chloro-2-methyl-5-((1-(pyridin-2-ylmethyl)piperidin-3-yl)amino)pyridazin-3(2H)-one (42 mg, 0.12 mmol) in 57% yield. ¹H NMR (¹H MHz, DMSO-d6) δ 8.48 (d, J=4.9 Hz, 1H), 7.86 (s, 1H), 7.74-7.79 (m, 1H), 7.46 (d, J=7.9 Hz, 1H), 7.25 (dd, J=5.0, 6.8 Hz, 1H), 5.99 (d, J=9.0 Hz, 1H), 3.85-3.90 (m, 1H), 3.64 (d, J=14.5 Hz, 1H), 3.62 (d, J=17.9 Hz, 1H), 3.57 (s, 3H), 2.65 (d, J=10.1 Hz, 1H), 2.45-2.55 (m, 1H), 2.32-2.42 (m, 2H), 1.63-1.69 (m, 2H), 1.51-1.57 (m, 2H). LCMS (ESI+): 334.0/336.0 (M+H, Cl pattern).

Example 34 racemic-5-((1-benzylpiperidin-3-yl)amino)-4-chloro-2-methylpyridazin-3(2H)-one

The title compound was synthesized in a fashion similar to Example 33 (4-chloro-5-((1-isopropylpiperidin-3-yl)amino)-2-methylpyridazin-3(2H)-one) using benzyl bromide instead of 2-(bromomethyl)pyridine hydrobromide. ¹H NMR (400 MHz, DMSO-d6) δ 7.83 (s, 1H), 7.30-7.31 (m, 4H), 7.22-7.25 (m, 1H), 5.93 (d, J=9.0 HZ, 1H), 3.86 (br. s, 1H), 3.56 (s, 3H), 3.54 (d, J=13.0 Hz, 1H), 3.46 (d, J=13.1 Hz, 1H), 2.49-2.56 (m, 1H), 2.30-2.43 (m, 3H), 1.50-1.65 (m, 4H). LCMS (ESI+): 333.1/335.1 (M+H, CI pattern)

Example 35 4-chloro-2-methyl-5-((1-((R)-1-phenylethyl)piperidin-3-yl)amino)pyridazin-3(2H)-one

Step 1: (S)-1-Phenylethyl Methanesulfonate

To a solution of (S)-1-phenylethanol (1.00 g, 8.19 mmol) in THF (10 mL) was added triethylamine (1.66 g, 16.38 mmol) at 0° C. Methanesulfonyl chloride (1.13 g, 9.83 mmol) was added and the mixture was stirred at room temperature for 4 hr. Water (10 mL) was added and THF was removed under reduced pressure. The residue was extracted with ethyl acetate (3×20 mL). The organic layer was washed with brine and dried over sodium sulfate. The solvent was removed under vacuum and the residue was purified by column chromatography on silica gel (eluted: hexanes/ethyl acetate=2/1) to give (S)-1-phenylethyl methanesulfonate (0.85 g, 4.26 mmol).

Step 2: 4-chloro-2-methyl-5-((1-((R)-1-phenylethyl)piperidin-3-yl)amino)pyridazin-3(2H)-one

4-chloro-2-methyl-5-(piperidin-3-ylamino)pyridazin-3(2H)-one dihydrochloride (0.100 g, 0.32 mmol) was suspended in acetonitrile (1 mL). Potassium carbonate (300 mg, 2.3 mmol) was added followed by (S)-1-phenylethyl methanesulfonate (0.1 g, 0.48 mmol) and stirred for 3 hours while heating at 40° C. The reaction mixture was filtered and evaporated under reduced pressure. The crude residue was purified by silica gel flash chromatography (0% to 100% 1:10:90 NH₄OH:MeOH:DCM in DCM). Pure fractions were evaporated to afford 4-chloro-2-methyl-5-((1-((R)-1-phenylethyl)piperidin-3-yl)amino)pyridazin-3(2H)-one (0.036 g, 0.1 mmol) in 31% yield. ¹H NMR (400 MHz, DMSO-d6) δ 7.81 (d, J=12.7 Hz, 1H), 7.30-7.32 (m, 4H), 7.22-7.23 (m, 1H), 5.91 (d, J=8.5 Hz, 1H), 3.80-3.86 (m, 1H), 3.60-3.65 (m, 1H), 3.57 (d, J=3.7 Hz, 3H), 2.51-2.57 (m, 1H), 2.25-2.47 (m, 3H), 1.46-1.60 (m, 4H), 1.21-1.31 (m, 3H). LCMS (ESI+): 347/349 (M+H, Cl pattern).

Example 36 4-chloro-2-methyl-5-((1-((S)-1-phenylethyl)piperidin-3-yl)amino)pyridazin-3(2H)-one

4-chloro-2-methyl-5-((1-((S)-1-phenylethyl)piperidin-3-yl)amino)pyridazin-3 (2H)-one was synthesized in a fashion similar to Example 35 (4-chloro-2-methyl-5-((1-((R)-1-phenylethyl)piperidin-3-yl)amino)pyridazin-3(2H)-one), using (R)-1-phenylethanol instead of (S)-1-phenylethanol as a starting material. ¹H NMR (400 MHz, DMSO-d6) δ 7.80 (d, J=12.7 Hz, 1H1), 7.30-7.33 (m, 4H), 7.22-7.23 (m, 1H), 5.91 (d, J=8.3 Hz, 1H), 3.75-3.90 (m, 1H), 3.60-3.66 (m, 1H), 3.56 (d, J=8.32 Hz, 3H), 2.51-2.57 (m, 1H), 2.25-2.47 (m, 3H), 1.36-1.68 (m, 4H), 1.25-1.35 (m, 3H). LCMS (ESI+): 347/349 (M+H, Cl pattern).

Examples 37-38 5-((1-benzylazepan-3-yl)amino)-4-chloro-2-methylpyridazin-3(2H)-one

Step 1: 3-((5-chloro-1-methyl-6-oxo-1,6-dihydropyridazin-4-yl)amino)azepan-2-one

4,5-dichloro-2-methylpyridazin-3(2H)-one (0.559 g, 3.12 mmol), 3-aminoazepan-2-one (0.600 g, 4.681 mmol), N.N-diisopropylethylamine (0.605 g, 4.68 mmol) and DMAc (1.3 mL) were charged in a sealable vial. The reaction mixture was heated to 120° C. for 30 min. The reaction was partitioned EtOAc and NaHCO₃. The organic phase was washed with brine, dried with Na₂SO₄, filtered and evaporated under reduced pressure. The crude residue was purified by silica gel flash chromatography (10% to 100% 1:10:90 NH₄OH:MeOH:DCM in DCM as eluent mixture). Two sets of fractions containing isomeric compounds were obtained; the later eluting fractions (most polar compound) were evaporated under reduced pressure to afford 3-((5-chloro-1-methyl-6-oxo-1,6-dihydropyridazin-4-yl)amino)azepan-2-one (0.302 g, 1.116 mmol) in 36% yield. LCMS (ESI+): 271/273 (M+H, C1 pattern).

Step 2: 5-(azepan-3-ylamino)-4-chloro-2-methylpyridazin-3(2H)-one

3-((5-chloro-1-methyl-6-oxo-1,6-dihydropyridazin-4-yl)amino)azepan-2-one (302 mg, 1.11 mmol) dissolved in THF (5 mL) The reaction mixture was cooled to 0° C. and borane (1M in THF) (2.22 mL, 2.22 mmol) was added with a syringe, dropwise over 5 minutes. The reaction mixture was heated to 70° C. for 1.5 hour. The reaction mixture was cooled to 0° C. MeOH (1 mL) was added at 0° C. and the reaction mixture was heated to 65° C. Reaction was stirred 30 minutes. The reaction mixture was evaporated under reduced pressure. The crude reaction mixture was purified by column chromatography (10% to 100% 1:10:90 NH₄OH:MeOH:DCM in DCM as eluent mixture) to afford two sets of fractions containing two regioisomers. The later eluting fractions (most polar compound) were evaporated under reduced pressure to afford 5-(azepan-3-ylamino)-4-chloro-2-methylpyridazin-3(2H)-one (0.05 g, 0.18 mmol) in 16% yield. LCMS (ESI+): 257 (M+H)

Step 3: 5-((1-benzylazepan-3-yl)amino)-4-chloro-2-methylpyridazin-3(2H)-one

5-(azepan-3-ylamino)-4-chloro-2-methylpyridazin-3(2H)-one (0.045 g, 0.19 mmol) was dissolved in acetonitrile (1.5 mL). DIEA (0.12 mL, 0.67 mmol) added followed by benzyl bromide (60 mg, 0.38 mmol). The reaction mixture was stirred for 3 hours while heating at 40° C. After removal of volatiles under reduced pressure and the crude residue was purified by flash chromatography (24 g-silica gel column, 0% to 100% 1:10:90 NH₄OH:MeOH:DCM in DCM as eluent mixture) to afford 5-((1-benzylazepan-3-yl)amino)-4-chloro-2-methylpyridazin-3(2H)-one (0.048 g, 0.14 mmol) in 74% yield. LCMS (M+H): 347/349 (M+H)

Step 4: (R)-5-((1-benzylazepan-3-yl)amino)-4-chloro-2-methylpyridazin-3(2H)-one and (S)-5-((1-benzylazepan-3-yl)amino)-4-chloro-2-methylpyridazin-3(2H)-one

The racemic mixture 5-((1-benzylazepan-3-yl)amino)-4-chloro-2-methylpyridazin-3(2H)-one was submitted to chiral separation on a PIC-100 Supercritical Fluid Chromatography instrument (Cellulose-4; 2×10 cm, 5 μm; Isocratic 50% Methanol w/0.1% NH₄OH; 100 bar; 40° C.; 70 mL/min; 220 nm) to afford Examples 37-38.

Example 39 (R)-4-chloro-2-methyl-5-((2,3,4,5-tetrahydro-1H-benzo[c]azepin-4-yl)amino)pyridazin-3(2H)-one

Step 1: (R)-3-(2-(aminomethyl)phenyl)-2-((tert-butoxycarbonyl)amino)propanoic acid

(R)-2-((tert-butoxycarbonyl)amino)-3-(2-cyanophenyl)propanoic acid (700 mg, 2.38 mmol) is dissolved placed in a pressure tube (capable of withstanding 60 psi) in Methanol, Raney Nickel added (100 mg), and the system was put under a 50 psi pressure of hydrogen for 24 hours. The reaction mixture was filtered on celite (caution! Flammable material when exposed to oxygen) using DCM as washing solvent. The filtrate was evaporated and dried under high vacuum to provide (R)-3-(2-(aminomethyl)phenyl)-2-((tert-butoxycarbonyl)amino)propanoic acid (700 mg, 2.38 mmol). LCMS (ESI+): 295 (M+H)

Step 2: (R)-tert-butyl (3-oxo-2,3,4,5-tetrahydro-1H-benzo[c]azepin-4-yl)carbamate

A mixture of (R)—N-tert-butyloxycarbonyl(2-aminomethylphenyl)alanine (700 mg, 2.38 mmol), N,N-dimethylformamide (2 mL), dichloromethane (10 mL), 1-hydroxy-7-azabenzotriazole (520 mg, 3.62 mmol), and 1-[3-(dimethylamino)propyl]-3-ethylcarbodiimide hydrochloride (360 mg, 1.87 mmol) was stirred at 25° C. for 1 h. The solvent was removed under vacuum and the residue was dissolved ethyl acetate (100 mL). This solution was washed sequentially with 1.0 M aqueous hydrochloric acid (50 mL), 1.0 M aqueous sodium hydroxide (50 mL), water (50 mL), and brine (50 mL), dried over anhydrous sodium sulfate and the filtered. The volatiles were evaporated under reduced pressure to afford (R)-tert-butyl (3-oxo-2,3,4,5-tetrahydro-1H-benzo[c]azepin-4-yl)carbamate (0.51 g, 1.86 mmol). LCMS (ESI+): 299 (M+Na)

Step 3: (R)-4-amino-4,5-dihydro-1H-benzo[c]azepin-3(2H)-one hydrochloride

(R)-4-((4-chloro-1-methyl-6-oxo-1,6-dihydropyridazin-5-yl)amino)-4,5-dihydro-1H-benzo[c]azepin-3(2H)-one (625 mg, 2.28 mmol) was dissolved in methanol (1 mL) and HCl (4 M in 1,4-dioxane) (2.3 ml, 9.1 mmol) was added. The reaction mixture was stirred for 3 hours at room temperature. The volatiles were evaporated under reduced pressure to afford (R)-4-amino-4,5-dihydro-1H-benzo[c]azepin-3(2H)-one hydrochloride (446 mg, 2.28 mmol) in quantitative yield. LCMS (ESI+): 177 (M+H).

Step 4: (R)-4-((5-chloro-1-methyl-6-oxo-1,6-dihydropyridazin-4-yl)amino)-4,5-dihydro-1H-benzo[c]azepin-3(2H)-one

4,5-dichloro-2-methylpyridazin-3(2H)-one hydrochloride (0.25 g, 1.3 mmol), N,N-diisopropylethylamine (0.867 g, 6.71 mmol), (R)-4-amino-4,5-dihydro-1H-benzo[c]azepin-3(2H)-one hydrochloride (0.446 g, 2.10 mmol) and DMAc (2 mL) were charged in a sealable vial. The reaction was heated to 120° C. for 30 min. The crude mixture was partitioned between EtOAc and NaHCO3 (aq., sat.). The organic phase were washed with brine, dried with Na₂SO₄, filtered and evaporated under reduced pressure. The crude residue was purified by flash chromatography (0% to 10% MeOH in DCM on a 24 g-silica gel column) to afford a mixture of two compounds, (R)-4-((5-chloro-1-methyl-6-oxo-1,6-dihydropyridazin-4-yl)amino)-4,5-dihydro-1H-benzo[c]azepin-3(2H)-one and (R)-4-((4-chloro-1-methyl-6-oxo-1,6-dihydropyridazin-5-yl)amino)-4,5-dihydro-1H-benzo[c]azepin-3(2H)-one (regioisomers). LCMS (ESI+): 319/321 (M+H, Cl pattern)

Step 5: (R)-4-chloro-2-methyl-5-((2,3,4,5-tetrahydro-1H-benzo[c]azepin-4-yl)amino)pyridazin-3(2H)-one

(R)-4-((5-chloro-1-methyl-6-oxo-1,6-dihydropyridazin-4-yl)amino)-4,5-dihydro-1H-benzo[c]azepin-3(2H)-one and (R)-4-((4-chloro-1-methyl-6-oxo-1,6-dihydropyridazin-5-yl)amino)-4,5-dihydro-1H-benzo[c]azepin-3(2H)-one (Mixture of regioisomers from previous step) (355 mg, 1.13 mmol) dissolved in THF (3 mL), cooled to 0° C., and borane solution was added (1M in THF) (1.13 mL, 4.52 mmol). Heated to 60° C. for 1 hour. The reaction mixture was cooled to 0° C. and methanol (1 mL) was added. The reaction mixture was heated to 55° C. for 1 hour. The crude reaction mixture was dry packed on silica. The compound was purified by flash chromatography (10% to 100% 1:10:90 NH₄OH:MeOH:DCM in DCM on a 40 g-silica column). Two sets of fractions were obtained. The later eluting (containing more polar compound) were combined and evaporated under reduced pressure to give (R)-4-chloro-2-methyl-5-((2,3,4,5-tetrahydro-1H-benzo[c]azepin-4-yl)amino)pyridazin-3(2H)-one (0.08 g, 0.26 mmol) (single regioisomer). LCMS (ESI+): 305 (M+H).

Step 6: (R)-4-chloro-2-methyl-5-((2-methyl-2,3,4,5-tetrahydro-1H-benzo[c]azepin-4-yl)amino)pyridazin-3(2H)-one

(R)-4-chloro-2-methyl-5-((2,3,4,5-tetrahydro-1H-benzo[c]azepin-4-yl)amino)pyridazin-3(2H)-one (80 mg, 0.26 mmol) was dissolved in MeOH (2 mL), acetic acid (50 μL) and formaldehyde (37% aqueous) (50 μL) were added. Reaction mixture was stirred 5 minutes. Sodium cyanoborohydride was added (30 mg, 0.52 mmol) and reaction mixture stirred 20 minutes. Volume increased to 3 mL with MeOH. Purified by preparative HPLC (water:acetonitrile with 0.1% trifluoroacetic acid, SunFire column). The pure fractions were frozen and lyophilized. The material was re-dissolved in acetonitrile:water, transferred to a 25 mL-flask, re-frozen and re-lyophilized to afford (R)-4-chloro-2-methyl-5-((2-methyl-2,3,4,5-tetrahydro-1H-benzo[c]azepin-4-yl)amino)pyridazin-3(2H)-one trifluoroacetic acid salt (0.05 g, 0.11 mmol). ¹H NMR (DMSO-d6) δ 10.68 (br. s., 1H), 9.98 (br. s., 1H), 8.01 (s, 1H), 7.32-7.46 (m, 4H), 6.82 (br. s., 1H), 4.45-4.56 (br. s., 3H), 3.95-4.01 (m, 1H), 3.61 (s, 3H), 3.22-3.27 (m, 1H), 3.00-3.15 (m, 2H), 2.75-2.84 (m, 2H). LCMS (ESI+): 319/321 (M+H, Cl pattern).

Example 40 4-chloro-2-methyl-5-((1-methylazocan-3-yl)amino)pyridazin-3(2H)-one

Step 1: 3-((5-chloro-1-methyl-6-oxo-1,6-dihydropyridazin-4-yl)amino)azocan-2-one

4,5-dichloro-2-methylpyridazin-3(2H)-one (200 mg, 1.117 mmol), 3-aminoazocan-2-one (155 mg, 1.09 mmol), N,N-diisopropylehtylamine (0.289 g, 2.23 mmol) and DMAc (1.3 mL) were charged in a sealable vial. The reaction was heated to 120° C. for 2 hours. The reaction mixture was partitioned between EtOAc and NaHCO₃ (aq., sat.). The crude product was purified by flash chromatography (10% to 100% 1:10:90 NH₄OH:MeOH:DCM in DCM, 24 g-silica gel column) to afford to sets of fractions containing regioisomers. The later eluting fractions (most polar isomer) was isolated after evaporation under reduced pressure to afford 3-((5-chloro-1-methyl-6-oxo-1,6-dihydropyridazin-4-yl)amino)azocan-2-one (0.235 g, 0.84 mmol) in 77% yield. LCMS (ESI+): 285/287 (M+H, Cl pattern).

Step 2: 5-(azocan-3-ylamino)-4-chloro-2-methylpyridazin-3(2H)-one

3-((5-chloro-1-methyl-6-oxo-1,6-dihydropyridazin-4-yl)amino)azocan-2-one (0.235 g, 0.84 mmol) was dissolved in THF (3 mL), cooled to 0° C., and borane added (1M in THF) (2.5 mL, 2.5 mmol). Heated to 60° C. for 1 hour. The reaction mixture was cooled to 0° C., methanol (1 mL) added. The reaction mixture was cooled to 0° C., methanol (1 mL) added. The reaction mixture was heated to 55° C. for 1 hour. The crude reaction mixture was dry packed on silica. The compound was purified by flash chromatography (10% to 100% 1:10:90 NH₄OH:MeOH:DCM in DCM, 24 g-silica gel column). The pure fractions were evaporated to afford 5-(azocan-3-ylamino)-4-chloro-2-methylpyridazin-3(2H)-one (0.17 g, 0.63 mmol) in 75% yield. LCMS (ESI+): 271/273 (M+H, Cl pattern).

Step 3: 4-chloro-2-methyl-5-((1-methylazocan-3-yl)amino)pyridazin-3(2H)-one

5-(azocan-3-ylamino)-4-chloro-2-methylpyridazin-3(2H)-one (170 mg, 0.63 mmol) in MeOH (2 ml) was dissolved, acetic acid (110 μL) and formaldehyde (37% aqueous) (160 μL) were added and stirred for 5 minutes. Sodium cyanoborohydride was added (80 mg, 0.52 mmol) and stirred 20 minutes. The reaction volume was increased to 3 mL with MeOH. The compound was purified by preparative reversed phase HPLC (water:acetonitrile with 0.1% trifluoroacetic acid, SunFire column). The pure fractions were frozen and lyophilized. The material was re-dissolved in acetonitrile:water, transferred to a 25 mL-flask, re-frozen and re-lyophilized to afford 4-chloro-2-methyl-5-((1-methylazocan-3-yl)amino)pyridazin-3(2H)-one as a trifluoroacetic acid salt (0.04 g, 0.09 mmol) in 14% yield. LCMS (ESI+): 285/287 (M+H, Cl pattern).

Example 41 Racemic-4-chloro-2-methyl-5-[[1-(3-phenylpropyl)-3-piperidyl]amino]pyridazin-3-one

To a 2 mL-vial was added 4-chloro-2-methyl-5-(3-piperidylamino)pyridazin-3-one dihydrochloride (54 mg, 0.17 mmol), 3-phenylpropanal (36 mg, 0.27 mmol), acetic acid (0.046 mL, 0.81 mmol), methanol (0.5 mL), 1,2-dichloroethane (0.5 mL) and SiliBond Cyanoborohydride resin (Silicycle cat# R66730B)(230 mg, 0.54 mmol). The vial was capped and stirred at 50° C. for 18 hours. The reaction was checked by LCMS and found to be completed. The reaction was filtered and the filtrate concentrated to dryness. The residue was dissolved in N,N-dimethylformamide and purified by reverse phase HPLC to afford pure (4-chloro-2-methyl-5-[[1-(3-phenylpropyl)-3-piperidyl]amino]pyridazin-3-one (17 mg) in 28% yield). ¹H NMR (400 MHz, DMSO-d₆) δ 7.90 (s, 1H), 7.33-7.10 (m, 6H), 5.93 (d, J=8.8 Hz, 1H), 3.90 (s, 1H), 3.59 (d, J=1.0 Hz, 3H), 2.67-2.57 (m, 2H), 2.43-2.23 (m, 4H), 1.72 (dd, J=8.2, 6.6 Hz, 2H), 1.65 (d, J=24.5 Hz, 2H), 1.59-1.45 (m, 2H). LCMS (ESI+): 361 (M+H).

The following examples were prepared using the method highlighted in Example 41.

Examples 42 to 56

42 4-chloro-5-((1-(2,6- ¹H NMR (400 MHz, DMSO-d₆) δ 7.85 (s, 369 difluorobenzyl)piperidin-3- 1H), 7.41 (t, J = 8.4 Hz, 1H), 7.10 (t, J = 7.9 Hz, yl)amino)-2- 2H), 5.91 (d, J = 8.9 Hz, 1H), 3.86 (s, methylpyridazin-3(2H)-one 1H), 3.64 (d, J = 1.4 Hz, 2H), 3.57 (s, 3H), 2.64 (d, J = 10.9 Hz, 1H), 2.45-2.27 (m, 3H), 1.69-1.42 (m, 4H). 43 4-chloro-5-[[1-[(4- ¹H NMR (400 MHz, DMSO-d₆) δ 7.84 (s, 376 dimethylaminophenyl)methyl]- 1H), 7.10 (d, J = 8.6 Hz, 2H), 6.67 (d, J = 8.6 Hz, 3-piperidyl]amino]-2- 2H), 5.91 (d, J = 8.8 Hz, 1H), methyl-pyridazin-3-one 3.86 (s, 1H), 3.57 (s, 3H), 3.51-3.32 (m, 2H), 2.90 (d, J = 3.6 Hz, 1H), 2.86 (s, 6H), 2.34 (d, J = 8.4 Hz, 3H), 1.56 (d, J = 38.2 Hz, 4H). 44 4-chloro-5-[[1-[[3- 399 (difluoromethoxy)phenyl]methyl]- 3-piperidyl]amino]-2- methyl-pyridazin-3-one 45 4-chloro-5-[[1-[(4-imidazol- 399 1-ylphenyl)methyl]-3- piperidyl]amino]-2-methyl- pyridazin-3-one 46 4-chloro-5-((1-(3,5- ¹H NMR (400 MHz, DMSO-d₆) δ 7.87 (s, 403 dichlorobenzyl)piperidin-3- 1H), 7.48 (s, 1H), 7.39 (d, J = 2.0 Hz, 2H), yl)amino)-2- 5.91 (d, J = 8.8 Hz, 1H), 3.91 (s, 1H), methylpyridazin-3(2H)-one 3.65-3.44 (m, 5H), 2.59 (d, J = 10.7 Hz, 1H), 2.39 (d, J = 16.0 Hz, 3H), 1.74-1.44 (m, 4H). 47 4-chloro-2-methyl-5-[[1-[(2- 418 morpholinophenyl)methyl]- 3- piperidyl]amino]pyridazin- 3-one 48 4-chloro-5-[[1-(1H- 323 imidazol-2-ylmethyl)-3- piperidyl]amino]-2-methyl- pyridazin-3-one 49 4-chloro-5-[[1-(1H- 323 imidazol-4-ylmethyl)-3- piperidyl]amino]-2-methyl- pyridazin-3-one 50 4-chloro-2-methyl-5-[[1- ¹H NMR (400 MHz, DMSO-d₆) δ 9.09 (s, 335 (pyrimidin-5-ylmethyl)-3- 1H), 8.75 (s, 2H), 7.87 (s, 1H), 5.93 (d, J = 8.9 Hz, piperidyl]amino]pyridazin- 1H), 3.88 (d, J = 9.0 Hz, 1H), 3-one 3.59 (d, J = 1.8 Hz, 2H), 3.58 (s, 3H), 2.66 (d, J = 9.0 Hz, 1H), 2.40-2.13 (m, 3H), 1.75-1.36 (m, 4H). 51 4-chloro-2-methyl-5-[[1-[(1- ¹H NMR (400 MHz, DMSO-d₆) δ 9.78 (s, 337 methylpyrazol-4- 1H), 7.86 (s, 1H), 7.54 (d, J = 6.7 Hz, 1H), yl)methyl]-3- 7.30 (s, 1H), 5.91 (s, 1H), 3.78 (d, J = 1.8 Hz, piperidyl]amino]pyridazin- 3H), 3.58 (s, 3H), 3.40 (s, 3H), 3-one 2.44-2.18 (m, 3H), 1.71-1.38 (m, 4H). 52 4-chloro-2-methyl-5-((1-((1- ¹H NMR (400 MHz, DMSO-d₆) δ 7.84 (s, 337 methyl-1H-imidazol-2- 1H), 7.08 (d, J = 1.2 Hz, 1H), 6.74 (d, J = 1.2 Hz, yl)methyl)piperidin-3- 1H), 5.84 (d, J = 8.8 Hz, 1H), yl)amino)pyridazin-3(2H)- 3.96-3.79 (m, 1H), 3.68 (s, 3H), 3.58 (s, 3H), one 3.55 (s, 2H), 2.55 (s, 1H), 2.41-2.22 (m, 3H), 1.74-1.38 (m, 4H). 53 4-chloro-2-methyl-5-[[1-[(5- ¹H NMR (400 MHz, DMSO-d₆) δ 8.30 (d, J = 2.1 Hz, 348 methyl-3-pyridyl)methyl]-3- 2H), 7.85 (s, 1H), 7.54 (s, 1H), piperidyl]amino]pyridazin- 5.92 (d, J = 8.9 Hz, 1H), 3.88 (s, 1H), 3-one 3.58 (s, 3H), 3.56-3.44 (m, 2H), 2.58 (d, J = 11.0 Hz, 1H), 2.34 (d, J = 8.4 Hz, 3H), 2.28 (d, J = 0.8 Hz, 3H), 1.74-1.44 (m, 4H). 54 4-chloro-5-[[1-[(4,5- 351 dimethyl-1H-imidazol-2- yl)methyl]-3- piperidyl]amino]-2-methyl- pyridazin-3-one 55 4-chloro-5-[[1-[[3-(4- ¹H NMR (400 MHz, DMSO-d₆) δ 435 chlorophenyl)-1,2,4- 8.08-7.99 (m, 2H), 7.92 (s, 1H), 7.72-7.57 (m, 2H), oxadiazol-5-yl]methyl]-3- 6.03 (d, J = 8.8 Hz, 1H), 4.08 (d, J = 6.4 Hz, piperidyl]amino]-2-methyl- 2H), 3.58 (s, 3H), 2.87 (d, J = 10.9 Hz, 1H), pyridazin-3-one 2.75-2.62 (m, 1H), 2.44 (d, J = 10.5 Hz, 3H), 1.78-1.42 (m, 4H). 56 4-chloro-5-[[1-[(4- ¹H NMR (400 MHz, DMSO-d₆) δ 7.85 (s, 351 fluorophenyl)methyl]-3- 1H), 7.35 (dd, J = 8.5, 5.8 Hz, 2H), 7.14 (t, J = 8.9 Hz, piperidyl]amino]-2-methyl- 2H), 5.94 (d, J = 8.8 Hz, 1H), pyridazin-3-one 3.87 (s, 1H), 3.57 (s, 3H), 3.50 (q, J = 13.3 Hz, 2H), 2.57 (d, J = 11.2 Hz, 1H), 2.46-2.22 (m, 3H), 1.76-1.41 (m, 4H).

Examples 57-58 (S)-4-chloro-2-methyl-5-((1-methylazepan-3-yl)amino)pyridazin-3(2H)-one and (R)-4-chloro-2-methyl-5-((1-methylazepan-3-yl)amino)pyridazin-3(2H)-one

(S)-4-chloro-2-methyl-5-((1-methylazepan-3-yl)amino)pyridazin-3(2H)-one and (R)-4-chloro-2-methyl-5-((1-methylazepan-3-yl)amino)pyridazin-3(2H)-one were obtained by performing chiral separation on Example 1 (racemic-4-chloro-2-methyl-5-((1-methylazepan-3-yl)amino)pyridazin-3(2H)-one) on a PIC-100 SFC supercritical fluid chromatography instrument (Chiralpak AD; 2×10 cm, 5 μm; 80% CO₂; Isocratic 20% Methanol w/0.1% NH₄OH; 100 bar; 40° C.; 70 mL/min; 220 nm).

Examples 59-60 (S)-4-chloro-2-methyl-5-((1-methylpiperidin-3-yl)amino)pyridazin-3(2H)-one and (R)-4-chloro-2-methyl-5-((1-methylpiperidin-3-yl)amino)pyridazin-3(2H)-one

(S)-4-chloro-2-methyl-5-((1-methylpiperidin-3-yl)amino)pyridazin-3(2H)-one and (R)-4-chloro-2-methyl-5-((1-methylpiperidin-3-yl)amino)pyridazin-3(2H)-one were obtained by performing chiral separation on Example 3 on a PIC-100 SFC supercritical fluid chromatography instrument (Chiralpak ID; 2×10 cm, 5 μm; 75% CO₂; Isocratic 25% Methanol w/0.1% NH₄OH; 100 bar; 40° C.; 70 mL/min; 220 nm).

Example 61 Biological Data IC₅₀ Measurements for Inhibitors Using PCAF AlphaLisa Binding Assay

His/Flag epitope tagged PCAF₇₁₉₋₈₃₂ bromodomain was cloned, expressed and purified to homogeneity in-house. PCAF bromodomain binding and inhibition of the compounds disclosed herein was assessed by monitoring the engagement of biotinylated small molecule ligand (known to bind to the PCAF bromodomain) with the target using the AlphaLisa technology (Perkin-Elmer). Specifically, in a 384 well ProxiPlate PCAF bromodomain (225 nM final) was combined with the biotinylated small molecule ligand (6 nM final) in 50 mM HEPES (pH 7.5), 75 mM NaCl, 1 mM TCEP, 0.01% (w/v) BSA, and 0.008% (w/v) Brij-35 either in the presence of DMSO (final 0.2% DMSO) or compound dilution series in DMSO. After 15 minute incubation at room temperature AlphaLisa streptavidin acceptor beads and AlphaLisa nickel chelate donor beads were added to a final concentration of 12.5 μg/mL each. After 90 minutes of equilibration plates were read on an Envision instrument and IC₅₀s calculated using a four parameter non-linear curve fit.

Data for representative compounds of formula (I) in the assay of Example 61 is provided in the following table.

TABLE Example PCAF IC₅₀ (μM) 1 0.062 2 1.22 3 0.085 4 0.187 5 0.480 6 0.492 7 0.0856 8 0.349 9 0.403 10 0.975 11 1.02 12 0.165 13 0.051 14 1.09 15 0.407 16 0.421 17 0.312 18 0.0496 19 1.98 20 0.0127 21 0.0365 22 0.0215 23 0.902 24 0.167 25 0.060 26 0.0348 27 0.144 28 0.175 29 0.0485 30 0.315 31 1.22 32 0.147 33 1.98 34 0.155 35 0.671 36 0.631 37 0.972 38 3.77 39 0.102 40 0.155 41 0.232 42 1.00 43 0.31 44 0.0949 45 0.386 46 0.278 47 0.921 48 0.379 49 0.178 50 0.625 51 0.371 52 1.41 53 0.441 54 1.44 55 0.466 56 0.139 57 0.0329 58 0.169 59 0.0512 60 0.235

While a number of embodiments have been described, these examples may be altered to provide other embodiments that utilize the compounds and methods described herein. Therefore, the scope of this invention is to be defined by the appended claims rather than by the specific embodiments that have been represented by way of example. 

1. A compound of formula (I), or a salt thereof:

wherein: R¹ is selected from the group consisting of methyl, chloro, and bromo; R² is C₁₋₄alkyl, C₂₋₄alkenyl, cyclopropyl, or cyclopropylmethyl; and R³ is a 3-12 membered saturated or partially unsaturated heterocyclyl, which heterocyclyl is optionally substituted with one or more groups independently selected from the group consisting of C₁₋₆alkyl, C₂₋₆₂alkenyl, C₂₋₆alkynyl, carbocyclyl, heterocyclyl, oxo, halo, —NO₂, —N(R^(b))₂, —CN, —C(O)—N(R^(b))₂, —S(O)—N(R^(b))₂, —S(O)₂—N(R^(b))₂, —O—R^(b), —S—R^(b), —O—C(O)—R^(b), —C(O)—R^(b), —C(O)—OR^(b), —S(O)—R^(b), —S(O)₂—R^(b), —N(R^(b))—C(O)—R^(b), —N(R^(b))—S(O)—R^(b), —N(R^(b))—C(O)—N(R^(b))₂, and —N(R^(b))—S(O)₂—R^(b), wherein any C₁₋₆alkyl, C₂₋₆alkenyl, C₂₋₆alkynyl, carbocyclyl, and heterocyclyl is optionally substituted with one or more groups independently selected from the group consisting of R^(b), oxo, halo, —NO₂, —N(R^(b))₂, —CN, —C(O)—N(R^(b))₂, —S(O)—N(R^(b))₂, —S(O)₂—N(R^(b))₂, —O—R^(b), —S—R^(b), —O—C(O)—R^(b), —C(O)—R^(b), —C(O)—O—R^(b), —S(O)—R^(b), —S(O)₂—R^(b), —N(R^(b))—C(O)—R^(b), —N(R^(b))—S(O)—R^(b), —N(R^(b))—C(O)—N(R^(b))₂, and —N(R^(b))—S(O)₂—R^(b); each R^(b) is independently selected from the group consisting of hydrogen, C₁₋₆alkyl, C₂₋₆alkenyl, C₂₋₆alkynyl, C₁₋₆alkoxy, carbocyclyl, and heterocyclyl, wherein each C₁₋₆alkyl, C₂₋₆alkenyl, C₂₋₆alkynyl, C₁₋₆alkoxy, carbocyclyl, and heterocyclyl is optionally substituted with one or more groups independently selected from the group consisting of R^(c), oxo, halo, —NO₂, —N(R^(c))₂, —CN, —C(O)—N(R^(c))₂, —S(O)—N(R^(c))₂, —S(O)₂—N(R^(c))₂, —O—R^(c), —S—R^(c), —O—C(O)—R^(c), —C(O)—R^(c), —C(O)—OR^(c), —S(O)—R^(c), —S(O)₂—R^(c), —N(R^(c))—C(O)—R^(c), —N(R^(c))—S(O)—R^(c), —N(R^(c))—C(O)—N(R^(c))₂, and —N(R^(c))—S(O)₂—R^(c); or two R^(c) are taken together with the nitrogen to which they are attached to form a heterocyclyl that is optionally substituted with one or more groups independently selected from the group consisting of oxo, halo and C₁₋₃alkyl that is optionally substituted with one or more groups independently selected from the group consisting of oxo and halo; and each R^(c) is independently selected from the group consisting of hydrogen, C₁₋₆alkyl, C₂₋₆alkenyl, C₂₋₆alkynyl, C₁₋₆alkoxy, carbocyclyl, and heterocyclyl, wherein each C₁₋₆alkyl, C₂₋₆alkenyl, C₂₋₆alkynyl, C₁₋₆alkoxy, carbocyclyl, and heterocyclyl is optionally substituted with one or more groups independently selected from the group consisting of oxo, halo, amino, hydroxy, C₁₋₆alkoxy, carbocyclyl, heterocyclyl, and C₁-C₆ alkyl that is optionally substituted with one or more groups independently selected from the group consisting of oxo and halo; or two R^(c) are taken together with the nitrogen to which they are attached to form a heterocyclyl that is optionally substituted with one or more groups independently selected from the group consisting of oxo, halo and C₁₋₃alkyl that is optionally substituted with one or more groups independently selected from the group consisting of oxo and halo; provided the compound is not selected from the group consisting of:


2. The compound of claim 1 wherein R¹ is chloro.
 3. The compound of claim 1 wherein R² is methyl, isopropyl, ethyl, cyclopropylmethyl, 2-buten-1-yl.
 4. The compound of claim 1 wherein R³ is a piperidyl ring or azepanyl ring, which piperidyl ring or azepanyl ring is optionally substituted with one or more groups independently selected from the group consisting of C₁₋₆alkyl, C₂₋₆alkenyl, C₂₋₆alkynyl, carbocyclyl, heterocyclyl, oxo, halo, —NO₂, —N(R^(b))₂, —CN, —C(O)—N(R^(b))₂, —S(O)—N(R^(b))₂, —S(O)₂—N(R^(b))₂, —O—R^(b), —S—R^(b), —O—C(O)—R^(b), —C(O)—R^(b), —C(O)—OR^(b), —S(O)—R^(b), —S(O)₂—R^(b), —N(R^(b))—C(O)—R^(b), —N(R^(b))—S(O)—R^(b), —N(R^(b))—C(O)—N(R^(b))₂, and —N(R^(b))—S(O)₂—R^(b), wherein any C₁₋₆alkyl, C₂₋₆alkenyl, C₂₋₆alkynyl, carbocyclyl, and heterocyclyl is optionally substituted with one or more groups independently selected from the group consisting of R^(b), oxo, halo, —NO₂, —N(R^(b))₂, —CN, —C(O)—N(R^(b))₂, —S(O)—N(R^(b))₂, —S(O)₂—N(R^(b))₂, —O—R^(b), —S—R^(b), —O—C(O)—R^(b), —C(O)—R^(b), —C(O)—O—R^(b), —S(O)—R^(b), —S(O)₂—R^(b), —N(R^(b))—C(O)—R^(b), —N(R^(b))—S(O)—R^(b), —N(R^(b))—C(O)—N(R^(b))₂, and —N(R^(b))—S(O)₂—R^(b).
 5. The compound of claim 1 wherein R³ is a piperidyl ring, which piperidyl ring is optionally substituted with one or more groups independently selected from the group consisting of C₁₋₆alkyl, C₂₋₆alkenyl, C₂₋₆alkynyl, carbocyclyl, heterocyclyl, oxo, halo, —NO₂, —N(R^(b))₂, —CN, —C(O)—N(R^(b))₂, —S(O)—N(R^(b))₂, —S(O)₂—N(R^(b))₂, —O—R^(b), —S—R^(b), —O—C(O)—R^(b), —C(O)—R^(b), —C(O)—OR^(b), —S(O)—R^(b), —S(O)₂—R^(b), —N(R^(b))—C(O)—R^(b), —N(R^(b))—S(O)—R^(b), —N(R^(b))—C(O)—N(R^(b))₂, and —N(R^(b))—S(O)₂—R^(b), wherein any C₁₋₆alkyl, C₂₋₆alkenyl, C₂₋₆alkynyl, carbocyclyl, and heterocyclyl is optionally substituted with one or more groups independently selected from the group consisting of R^(b), oxo, halo, —NO₂, —N(R^(b))₂, —CN, —C(O)—N(R^(b))₂, —S(O)—N(R^(b))₂, —S(O)₂—N(R^(b))₂, —O—R^(b), —S—R^(b), —O—C(O)—R^(b), —C(O)—R^(b), —C(O)—O—R^(b), —S(O)—R^(b), —S(O)₂—R^(b), —N(R^(b))—C(O)—R^(b), —N(R^(b))—S(O)—R^(b), —N(R^(b))—C(O)—N(R^(b))₂, and —N(R^(b))—S(O)₂—R^(b);
 6. The compound of claim 1 wherein R³ is a azepanyl ring, which azepanyl ring is optionally substituted with one or more groups independently selected from the group consisting of C₁₋₆alkyl, C₂₋₆alkenyl, C₂₋₆alkynyl, carbocyclyl, heterocyclyl, oxo, halo, —NO₂, —N(R^(b))₂, —CN, —C(O)—N(R^(b))₂, —S(O)—N(R^(b))₂, —S(O)₂—N(R^(b))₂, —O—R^(b), —S—R^(b), —O—C(O)—R^(b), —C(O)—R^(b), —C(O)—OR^(b), —S(O)—R^(b), —S(O)₂—R^(b), —N(R^(b))—C(O)—R^(b), —N(R^(b))—S(O)—R^(b), —N(R^(b))—C(O)—N(R^(b))₂, and —N(R^(b))—S(O)₂—R^(b), wherein any C₁₋₆alkyl, C₂₋₆alkenyl, C₂₋₆alkynyl, carbocyclyl, and heterocyclyl is optionally substituted with one or more groups independently selected from the group consisting of R^(b), oxo, halo, —NO₂, —N(R^(b))₂, —CN, —C(O)—N(R^(b))₂, —S(O)—N(R^(b))₂, —S(O)₂—N(R^(b))₂, —O—R^(b), —S—R^(b), —O—C(O)—R^(b), —C(O)—R^(b), —C(O)—O—R^(b), —S(O)—R^(b), —S(O)₂—R^(b), —N(R^(b))—C(O)—R^(b), —N(R^(b))—S(O)—R^(b), —N(R^(b))—C(O)—N(R^(b))₂, and —N(R^(b))—S(O)₂—R^(b).
 7. The compound of claim 1 wherein R³ is a piperidyl ring or azepanyl ring, which piperidyl ring or azepanyl ring is optionally substituted with one or more groups independently selected from the group consisting of C₁₋₆alkyl, wherein any C₁₋₆alkyl is optionally substituted with one or more groups independently selected from the group consisting of R^(b), oxo, halo, —NO₂, —N(R^(b))₂, —CN, —C(O)—N(R^(b))₂, —S(O)—N(R^(b))₂, —S(O)₂—N(R^(b))₂, —O—R^(b), —S—R^(b), —O—C(O)—R^(b), —C(O)—R^(b), —C(O)—O—R^(b), —S(O)—R^(b), —S(O)₂—R^(b), —N(R^(b))—C(O)—R^(b), —N(R^(b))—S(O)—R^(b), —N(R^(b))—C(O)—N(R^(b))₂, and —N(R^(b))—S(O)₂—R^(b).
 8. The compound of claim 1 wherein R³ is a piperidyl ring, which piperidyl ring is optionally substituted with one or more groups independently selected from the group consisting of C₁₋₆alkyl, wherein any C₁₋₆alkyl is optionally substituted with one or more groups independently selected from the group consisting of R^(b), oxo, halo, —NO₂, —N(R^(b))₂, —CN, —C(O)—N(R^(b))₂, —S(O)—N(R^(b))₂, —S(O)₂—N(R^(b))₂, —O—R^(b), —S—R^(b), —O—C(O)—R^(b), —C(O)—R^(b), —C(O)—O—R^(b), —S(O)—R^(b), —S(O)₂—R^(b), —N(R^(b))—C(O)—R^(b), —N(R^(b))—S(O)—R^(b), —N(R^(b))—C(O)—N(R^(b))₂, and —N(R^(b))—S(O)₂—R^(b).
 9. The compound of claim 1 wherein R³ is a azepanyl ring, which azepanyl ring is optionally substituted with one or more groups independently selected from the group consisting of C₁₋₆alkyl, wherein any C₁₋₆alkyl is optionally substituted with one or more groups independently selected from the group consisting of R^(b), oxo, halo, —NO₂, —N(R^(b))₂, —CN, —C(O)—N(R^(b))₂, —S(O)—N(R^(b))₂, —S(O)₂—N(R^(b))₂, —O—R^(b), —S—R^(b), —O—C(O)—R^(b), —C(O)—R^(b), —C(O)—O—R^(b), —S(O)—R^(b), —S(O)₂—R^(b), —N(R^(b))—C(O)—R^(b), —N(R^(b))—S(O)—R^(b), —N(R^(b))—C(O)—N(R^(b))₂, and —N(R^(b))—S(O)₂—R^(b).
 10. The compound of claim 1 wherein: R¹ is selected from the group consisting of methyl, chloro, and bromo; R² is C₁₋₄alkyl, C₂₋₄alkenyl, cyclopropyl, or cyclopropylmethyl; and R³ is a piperidyl ring or azepanyl ring, which piperidyl ring or azepanyl ring is optionally substituted with one or more groups independently selected from the group consisting of C₁₋₆alkyl, wherein any C₁₋₆alkyl is optionally substituted with one or more groups independently selected from the group consisting of R^(b).
 11. The compound of claim 1 wherein: R¹ is selected from the group consisting of methyl, chloro, and bromo; R² is C₁₋₄alkyl, C₂₋₄alkenyl, cyclopropyl, or cyclopropylmethyl; and R³ is a piperidyl ring, which piperidyl ring is optionally substituted with one or more groups independently selected from the group consisting of C₁₋₆alkyl, wherein any C₁₋₆alkyl is optionally substituted with one or more groups independently selected from the group consisting of R^(b).
 12. The compound of claim 1 wherein: R¹ is selected from the group consisting of methyl, chloro, and bromo; R² is C₁₋₄alkyl, C₂₋₄alkenyl, cyclopropyl, or cyclopropylmethyl; and R³ is a azepanyl ring, which azepanyl ring is optionally substituted with one or more groups independently selected from the group consisting of C₁₋₆alkyl, wherein any C₁₋₆alkyl is optionally substituted with one or more groups independently selected from the group consisting of R^(b).
 13. The compound of claim 1 wherein R³ is selected from the group consisting of:


14. The compound of claim 1 wherein R³ is selected from the group consisting of:


15. The compound of claim 1, which is selected from the group consisting of:

or a salt thereof.
 16. A composition comprising a compound of formula (I) as described in claim 1, or a pharmaceutically acceptable salt thereof, and a pharmaceutically acceptable adjuvant, carrier, or vehicle.
 17. The composition according to claim 16, in combination with an additional therapeutic agent.
 18. (canceled)
 19. A method for treating a PCAF mediated disorder or a GCN5 mediated disorder in an animal comprising administering to the animal a compound of formula (I), or a pharmaceutically acceptable salt thereof:

wherein: R¹ is selected from the group consisting of methyl, chloro, and bromo; R² is C₁₋₄alkyl, C₂₋₄alkenyl, cyclopropyl, or cyclopropylmethyl; and R³ is a 3-12 membered saturated or partially unsaturated heterocyclyl, which heterocyclyl is optionally substituted with one or more groups independently selected from the group consisting of C₁₋₆alkyl, C₂₋₆alkenyl, C₂₋₆alkynyl, carbocyclyl, heterocyclyl, oxo, halo, —NO₂, —N(R^(b))₂, —CN, —C(O)—N(R^(b))₂, —S(O)—N(R^(b))₂, —S(O)₂—N(R^(b))₂, —O—R^(b), —S—R^(b), —O—C(O)—R^(b), —C(O)—R^(b), —C(O)—OR^(b), —S(O)—R^(b), —S(O)₂—R^(b), —N(R^(b))—C(O)—R^(b), —N(R^(b))—S(O)—R^(b), —N(R^(b))—C(O)—N(R^(b))₂, and —N(R^(b))—S(O)₂—R^(b), wherein any C₁₋₆alkyl, C₂₋₆alkenyl, C₂₋₆alkynyl, carbocyclyl, and heterocyclyl is optionally substituted with one or more groups independently selected from the group consisting of R^(b), oxo, halo, —NO₂, —N(R^(b))₂, —CN, —C(O)—N(R^(b))₂, —S(O)—N(R^(b))₂, —S(O)₂—N(R^(b))₂, —O—R^(b), —S—R^(b), —O—C(O)—R^(b), —C(O)—R^(b), —C(O)—O—R^(b), —S(O)—R^(b), —S(O)₂—R^(b), —N(R^(b))—C(O)—R^(b), —N(R^(b))—S(O)—R^(b), —N(R^(b))—C(O)—N(R^(b))₂, and —N(R^(b))—S(O)₂—R^(b); each R^(b) is independently selected from the group consisting of hydrogen, C₁₋₆alkyl, C₂₋₆alkenyl, C₂₋₆alkynyl, C₁₋₆alkoxy, carbocyclyl, and heterocyclyl, wherein each C₁₋₆alkyl, C₂₋₆alkenyl, C₂₋₆alkynyl, C₁₋₆alkoxy, carbocyclyl, and heterocyclyl is optionally substituted with one or more groups independently selected from the group consisting of R^(c), oxo, halo, —NO₂, —N(R^(c))₂, —CN, —C(O)—N(R^(c))₂, —S(O)—N(R^(c))₂, —S(O)₂—N(R^(c))₂, —O—R^(c), —S—R^(c), —O—C(O)—R^(c), —C(O)—R^(c), —C(O)—OR^(c), —S(O)—R^(c), —S(O)₂—R^(c), —N(R^(c))—C(O)—R^(c), —N(R^(c))—S(O)—R^(c), —N(R^(c))—C(O)—N(R^(c))₂, and —N(R^(c))—S(O)₂—R^(c); or two R^(c) are taken together with the nitrogen to which they are attached to form a heterocyclyl that is optionally substituted with one or more groups independently selected from the group consisting of oxo, halo and C₁₋₃alkyl that is optionally substituted with one or more groups independently selected from the group consisting of oxo and halo; and each R^(c) is independently selected from the group consisting of hydrogen, C₁₋₆alkyl, C₂₋₆alkenyl, C₂₋₆alkynyl, C₁₋₆alkoxy, carbocyclyl, and heterocyclyl, wherein each C₁₋₆alkyl, C₂₋₆alkenyl, C₂₋₆alkynyl, C₁₋₆alkoxy, carbocyclyl, and heterocyclyl is optionally substituted with one or more groups independently selected from the group consisting of oxo, halo, amino, hydroxy, C₁₋₆alkoxy, carbocyclyl, heterocyclyl, and C₁-C₆ alkyl that is optionally substituted with one or more groups independently selected from the group consisting of oxo and halo; or two R^(c) are taken together with the nitrogen to which they are attached to form a heterocyclyl that is optionally substituted with one or more groups independently selected from the group consisting of oxo, halo and C₁₋₃alkyl that is optionally substituted with one or more groups independently selected from the group consisting of oxo and halo. 20-30. (canceled)
 31. A method of a) increasing efficacy of a cancer treatment comprising a cytotoxic agent in an animal, b) delaying or preventing development of cancer resistance to a cytotoxic agent in an animal, or c) extending the duration of response to a cancer therapy in an animal comprising administering to the animal an effective amount of a compound of formula (I), or a pharmaceutically acceptable salt thereof:

wherein: R¹ is selected from the group consisting of methyl, chloro, and bromo; R² is C₁₋₄alkyl, C₂₋₄alkenyl, cyclopropyl, or cyclopropylmethyl; and R³ is a 3-12 membered saturated or partially unsaturated heterocyclyl, which heterocyclyl is optionally substituted with one or more groups independently selected from the group consisting of C₁₋₆alkyl, C₂₋₆alkenyl, C₂₋₆alkynyl, carbocyclyl, heterocyclyl, oxo, halo, —NO₂, —N(R^(b))₂, —CN, —C(O)—N(R^(b))₂, —S(O)—N(R^(b))₂, —S(O)₂—N(R^(b))₂, —O—R^(b), —S—R^(b), —O—C(O)—R^(b), —C(O)—R^(b), —C(O)—OR^(b), —S(O)—R^(b), —S(O)₂—R^(b), —N(R^(b))—C(O)—R^(b), —N(R^(b))—S(O)—R^(b), —N(R^(b))—C(O)—N(R^(b))₂, and —N(R^(b))—S(O)₂—R^(b), wherein any C₁₋₆alkyl, C₂₋₆alkenyl, C₂₋₆alkynyl, carbocyclyl, and heterocyclyl is optionally substituted with one or more groups independently selected from the group consisting of R^(b), oxo, halo, —NO₂, —N(R^(b))₂, —CN, —C(O)—N(R^(b))₂, —S(O)—N(R^(b))₂, —S(O)₂—N(R^(b))₂, —O—R^(b), —S—R^(b), —O—C(O)—R^(b), —C(O)—R^(b), —C(O)—O—R^(b), —S(O)—R^(b), —S(O)₂—R^(b), —N(R^(b))—C(O)—R^(b), —N(R^(b))—S(O)—R^(b), —N(R^(b))—C(O)—N(R^(b))₂, and —N(R^(b))—S(O)₂—R^(b); each R^(b) is independently selected from the group consisting of hydrogen, C₁₋₆alkyl, C₂₋₆alkenyl, C₂₋₆alkynyl, C₁₋₆alkoxy, carbocyclyl, and heterocyclyl, wherein each Cl-alkyl, C₂₋₆alkenyl, C₂₋₆alkynyl, C₁₋₆alkoxy, carbocyclyl, and heterocyclyl is optionally substituted with one or more groups independently selected from the group consisting of R^(c), oxo, halo, —NO₂, —N(R^(c))₂, —CN, —C(O)—N(R^(c))₂, —S(O)—N(R^(c))₂, —S(O)₂—N(R^(c))₂, —O—R^(c), —S—R^(c), —O—C(O)—R^(c), —C(O)—R^(c), —C(O)—OR^(c), —S(O)—R^(c), —S(O)₂—R^(c), —N(R^(c))—C(O)—R^(c), —N(R^(c))—S(O)—R^(c), —N(R^(c))—C(O)—N(R^(c))₂, and —N(R^(c))—S(O)₂—R^(c); or two R^(c) are taken together with the nitrogen to which they are attached to form a heterocyclyl that is optionally substituted with one or more groups independently selected from the group consisting of oxo, halo and C₁₋₃alkyl that is optionally substituted with one or more groups independently selected from the group consisting of oxo and halo; and each R^(c) is independently selected from the group consisting of hydrogen, C₁₋₆alkyl, C₂₋₆alkenyl, C₂₋₆alkynyl, C₁₋₆alkoxy, carbocyclyl, and heterocyclyl, wherein each C₁₋₆alkyl, C₂₋₆alkenyl, C₂₋₆alkynyl, C₁₋₆alkoxy, carbocyclyl, and heterocyclyl is optionally substituted with one or more groups independently selected from the group consisting of oxo, halo, amino, hydroxy, C₁₋₆alkoxy, carbocyclyl, heterocyclyl, and C₁-C₆ alkyl that is optionally substituted with one or more groups independently selected from the group consisting of oxo and halo; or two R^(c) are taken together with the nitrogen to which they are attached to form a heterocyclyl that is optionally substituted with one or more groups independently selected from the group consisting of oxo, halo and C₁₋₃alkyl that is optionally substituted with one or more groups independently selected from the group consisting of oxo and halo. 32-34. (canceled)
 35. A method of treating cancer in an individual comprising administering to the individual (a) compound of formula (I), or a pharmaceutically acceptable salt thereof:

wherein: R¹ is selected from the group consisting of methyl, chloro, and bromo; R² is C₁₋₄alkyl, C₂₋₄alkenyl, cyclopropyl, or cyclopropylmethyl; and R³ is a 3-12 membered saturated or partially unsaturated heterocyclyl, which heterocyclyl is optionally substituted with one or more groups independently selected from the group consisting of C₁₋₆alkyl, C₂₋₆alkenyl, C₂₋₆alkynyl, carbocyclyl, heterocyclyl, oxo, halo, —NO₂, —N(R^(b))₂, —CN, —C(O)—N(R^(b))₂, —S(O)—N(R^(b))₂, —S(O)₂—N(R^(b))₂, —O—R^(b), —S—R^(b), —O—C(O)—R^(b), —C(O)—R^(b), —C(O)—OR^(b), —S(O)—R^(b), —S(O)₂—R^(b), —N(R^(b))—C(O)—R^(b), —N(R^(b))—S(O)—R^(b), —N(R^(b))—C(O)—N(R^(b))₂, and —N(R^(b))—S(O)₂—R^(b), wherein any C₁₋₆alkyl, C₂₋₆alkenyl, C₂₋₆alkynyl, carbocyclyl, and heterocyclyl is optionally substituted with one or more groups independently selected from the group consisting of R^(b), oxo, halo, —NO₂, —N(R^(b))₂, —CN, —C(O)—N(R^(b))₂, —S(O)—N(R^(b))₂, —S(O)₂—N(R^(b))₂, —O—R^(b), —S—R^(b), —O—C(O)—R^(b), —C(O)—R^(b), —C(O)—O—R^(b), —S(O)—R^(b), —S(O)₂—R^(b), —N(R^(b))—C(O)—R^(b), —N(R^(b))—S(O)—R^(b), —N(R^(b))—C(O)—N(R^(b))₂, and —N(R^(b))—S(O)₂—R^(b); each R^(b) is independently selected from the group consisting of hydrogen, C₁₋₆alkyl, C₂₋₆alkenyl, C₂₋₆alkynyl, C₁₋₆alkoxy, carbocyclyl, and heterocyclyl, wherein each C₁₋₆alkyl, C₂₋₆alkenyl, C₂₋₆alkynyl, C₁₋₆alkoxy, carbocyclyl, and heterocyclyl is optionally substituted with one or more groups independently selected from the group consisting of R^(c), oxo, halo, —NO₂, —N(R^(c))₂, —CN, —C(O)—N(R^(c))₂, —S(O)—N(R^(c))₂, —S(O)₂—N(R^(c))₂, —O—R^(c), —S—R^(c), —O—C(O)—R^(c), —C(O)—R^(c), —C(O)—OR^(c), —S(O)—R^(c), —S(O)₂—R^(c), —N(R^(c))—C(O)—R^(c), —N(R^(c))—S(O)—R^(c), —N(R^(c))—C(O)—N(R^(c))₂, and —N(R^(c))—S(O)₂—R^(c); or two R^(c) are taken together with the nitrogen to which they are attached to form a heterocyclyl that is optionally substituted with one or more groups independently selected from the group consisting of oxo, halo and C₁₋₃alkyl that is optionally substituted with one or more groups independently selected from the group consisting of oxo and halo; and each R is independently selected from the group consisting of hydrogen, C₁₋₆alkyl, C₂₋₆alkenyl, C₂₋₆alkynyl, C₁₋₆alkoxy, carbocyclyl, and heterocyclyl, wherein each C₁₋₆alkyl, C₂₋₆alkenyl, C₂₋₆alkynyl, C₁₋₆alkoxy, carbocyclyl, and heterocyclyl is optionally substituted with one or more groups independently selected from the group consisting of oxo, halo, amino, hydroxy, C₁₋₆alkoxy, carbocyclyl, heterocyclyl, and C₁-C₆ alkyl that is optionally substituted with one or more groups independently selected from the group consisting of oxo and halo; or two R^(c) are taken together with the nitrogen to which they are attached to form a heterocyclyl that is optionally substituted with one or more groups independently selected from the group consisting of oxo, halo and C₁₋₃alkyl that is optionally substituted with one or more groups independently selected from the group consisting of oxo and halo; and (b) a cytotoxic agent. 36-47. (canceled) 